[i]

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[iii]

State of New York—Department of Agriculture

Eighteenth Annual Report—Vol. 3—Part II

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[v]

THE
PLUMS OF NEW YORK

BY

U. P. HEDRICK

ASSISTED BY

R. WELLINGTON
O. M. TAYLOR
W. H. ALDERMAN
M. J. DORSEY

Report of the New York Agricultural Experiment Station for the Year 1910

II

ALBANY

J. B. LYON COMPANY, STATE PRINTERS

1911

The Plums of New York is the third monograph of the fruits of this region published by the New York Agricultural Experiment Station. The aims of these books have been stated in full in The Grapes of New York, but it is considered best to re-state some of these briefly and to indicate some features in which the book on plums differs from the one on grapes.

Broadly speaking, the aim has been to make The Plums of New York a record of our present knowledge of cultivated plums. The book has been written for New York but its contents are so general in character that the work applies to the whole country and more or less to the world. The first chapter is a historical account and a botanical classification of plums; the second, a discussion of the present status of plum-growing in America; while the third and fourth are devoted to varieties of plums. The first and last two of these chapters contain the synonymy and bibliography of the species and varieties of plums. In the foot-notes running through the book biographical sketches are given of the persons who have contributed most to plum culture in America; here may be found also matters pertaining to plums not properly included in the text but necessary for its best understanding. Important varieties, so considered from various standpoints, with the bark and the flowers of several species, are illustrated in colors.

The Plums of New York is a horticultural and not a botanical work. But in a study of the fruit from a horticultural standpoint one must of necessity consider botanical relationships. It is hoped that in this enforced systematic study of plums, however, something has been added to the botanical knowledge of this fruit. In classifying the varieties and species, to show their characters and relationships, the author has chosen to dispose of the groups in accordance with his own views though the arrangement adopted is, for most part, scarcely more than a modification of existing classifications.

Attention must be called to the indefiniteness of species and varieties of plums due chiefly to the extreme responsiveness of the plants to environment. On each side of the specific or varietal types there are wide ranges of variation. Since the relationships between types are often very close it[vi] is impossible to avoid some confusion in characters, for outliers of the types cannot but overlap. It might be well said that these outliers are connecting links and that groups so connected should be combined, but this would make specific division of the genus and varietal division of the species almost impossible. The groups must, therefore, be separated along more or less arbitrary lines. But such arbitrary separation does not prevent natural groups, if nature be broadly interpreted.

The chief value of the work in hand lies in its discussion of varieties. In the descriptions the aim has been to give as tersely as possible an idea of all of the characters of the plums described. With very few exceptions the technical descriptions of varieties are original and were made by those who have taken active part in the preparation of this book. Nearly all of the varieties having full descriptions grow on the Station grounds but whenever possible specimens of each variety from different localities have been compared with those growing here.

A special effort has been made to give as exactly as possible the regions in which the species and varieties of plums grow. Such an effort is made under the belief that this knowledge is of great value in the study of the factors which govern the distribution of wild and domesticated plants. If the boundaries of the regions in which a few scores of varieties of the several fruits grow can be accurately established valuable generalizations can be drawn regarding life zones and plant distribution.

The reader should know what considerations have governed the selection of varieties for color-plates and full descriptions. These are: (1) The known value of the variety for the commercial or amateur grower. (2) The probable value of new varieties. (3) To furnish data for the plum-breeder; to show combinations of species or varieties, or new characters, or the range in variation. (4) Some sorts have been described because of historical value—to better show what the trend of plum evolution has been. (5) To indicate the relationships of species and varieties. The varieties are divided into three groups according to their importance as gauged from the standpoints given above.

In botanical nomenclature the code adopted by the American botanists in Philadelphia in 1904 and modified by the International Botanical Congress at Vienna in 1905, has been used. For horticultural names, lacking a better code, the revised rules of the American Pomological Society have been followed, though in a few cases we have not seen fit to follow the rules of this society, as the changes required by their strict observance[vii] would have brought much confusion. Only those who have to work with a great number of varieties of fruit can know the chaotic conditions of our pomological nomenclature. One of the aims of the work in hand is to set straight in some degree the great confusion in plum names.

All synonyms of varieties have been given so far as they could be determined but it did not seem worth while to give all of the references to be found even in standard plum literature. Fewer of these are listed for the leading varieties than in the books on apples or grapes which have preceded, only such being given as have been found of use by the writers or thought of possible use to future plum students. On the other hand some references have been given for all varieties, a task not attempted in The Grapes of New York.

As in the preceding books the color-plates have been given much attention. Work and expense have not been spared to make the plates the best possible with the present knowledge of color-printing. Yet the illustrations are not exact reproductions. The colors are, at best, only approximations; for it is impossible by mechanical processes to reproduce Nature’s delicate tints and shades. The camera does not take colors as the human eye sees them; and the maker of the copper plate can not quite reproduce all that the camera has taken. The colors then depend on the judgment of the printer, who by selecting and mingling colored inks, reproduces as nearly as his materials permit, the shades in his eye and mind; but no two persons see exactly the same colors in any object; so his conception may differ much from that of the horticulturist or artist who saw the original plum, as do theirs from each other. Still it is hoped that the color-plates will be of great service in illustrating the text. All of the plums from which the plates were made came from the Station grounds; the illustrations, with a few exceptions which are noted, are of life size, as grown under the conditions existing at this place, and as far as possible all are from specimens of average size and color.

Acknowledgments are due in particular to the plum-growers of New York who have furnished much information for The Plums of New York; to numerous institutions in all parts of the United States who have loaned botanical specimens; to Professor Charles Sprague Sargent for advice, information and the use of the Arnold Arboretum library and herbarium; to W. F. Wight of the United States Department of Agriculture, who has given most valuable assistance in describing the species of plums and in giving their range; to the Station Editor, F. H. Hall, who has had[viii] charge of the proof-reading; to Zeese-Wilkinson and Company, New York City, for their care and skill in making the color-plates; and to the J. B. Lyon Company, Albany, New York, for their careful work in the mechanical construction of the book.

U. P. HEDRICK,
Horticulturist, New York Agricultural Experiment Station.

THE GENUS PRUNUS

The great genus Prunus includes plums, cherries, almonds, apricots, peaches, and the evergreen cherries or cherry laurels. Its widely distributed species number a hundred or more for the world, nearly all of which belong north of the equator. The species of the genus are widely distributed in both the eastern and western hemispheres, the flora of eastern America and of western Asia being especially rich in species and individuals. For most part the species of Prunus belong to the Temperate Zone, but several of the evergreen cherries, usually grouped in a section under Laurocerasus, are found in the tropics and sub-tropics.

The species cultivated for their edible fruits are found only in the Temperate Zone of the Northern Hemisphere. Of these the peach and the almond are believed to have come from eastern and southeastern Asia; the apricot is thought to be a native of northern China; the wild forms of the cultivated cherries are Eurasian plants, very generally distributed in the regions to the northward where the two continents meet. The habitats of the cultivated plums are given in detail in the text that follows, as Asia, Europe and America. Presumably the genus had its origin in some of the above regions; but where the center is from which the species radiated can never be known. Indeed, with present knowledge it cannot be said in what region Prunus has most species, is most productive of individuals, or shows highest development and greatest variability,—facts which might give some evidence as to the origin of the genus. It is probable that the greatest number of combinations of the above evidences can be shown for Asia and more especially for the Eurasian region, where Europe and Asia meet; yet North America has two score or more indigenous species about half of which are arborescent.

The history of the genus Prunus is one of continual changes. Of the botanists who have done most toward classifying plants, Ray, Tournefort, Dillenius and Boerhaave, pre-Linnaean botanists, placed only the plum[2] in Prunus. Linnaeus adopted the name used by his predecessors for the plum alone, for a genus in which he also placed plums and cherries. Adanson and Jussieu returned to the pre-Linnaean classification but Gaertner followed the grouping of Linnaeus. Necker, DeCandolle, Roemer and Decaisne held that the plum alone belongs in Prunus. Bentham & Hooker, Gray and his co-workers in the several revisions of his botany, and Engler & Prantl, great authorities of the Nineteenth Century, extend the genus to include all of the stone-fruits. On the other hand, Britton and Brown, in their recent flora of northern United States and of Canada restrict the group to plums and cherries. Horticulturists have been less divided in their opinions than the botanists and have very generally placed all of the stone-fruits in one genus. The diversity of views as to what plants belong in Prunus, indicated above, suggests that the differences separating the several stone-fruits may not be many nor very distinct. This is true, and makes necessary a discussion of the characters which distinguish these fruits.

The flowers of true plums are borne on stems in fascicled umbels and appear either before the leaves or with or after them. Flowers of the cultivated cherries are similarly borne, though the fascicles are corymbose rather than umbelliferous. But apricot, peach and almond flowers are stemless or nearly so and solitary or borne in pairs appearing before the leaves.

The fruits of plums and cherries are globular or oblong, fleshy, very juicy, with smooth or slightly hairy skins. Peaches, apricots and almonds are more sulcate or grooved than plums and cherries and the first two have juicy flesh, but that of the almond is dry and hard or skin-like, splitting at maturity thereby liberating the stone; these last three fruits are distinguished from plums and cherries by having very pubescent or velvety skins though rarely, as in the nectarine, a botanical variety of the peach, and in a few cultivated apricots, the skins are smooth.

The stone of the plum is usually compressed, longer than broad, smooth or roughened, thickish and with an acute margin along the ventral suture and thinnish or grooved on the dorsal suture. The stone of the cherry is usually globular, always much thickened, smooth or a very little roughened, ridged and grooved on the ventral suture, with a thin, scarcely raised sharp margin on the dorsal suture. The stone of the apricot is similar to that of the plum though thicker walled, with a more conspicuous winged margin, and is sometimes pitted. The stone of the peach is compressed, usually with very thick walls, much roughened and deeply pitted. In[3] the almond the stone resembles in general characters the peach-stone, but all almond shells are more or less porous and often fibrous on the inner surfaces. The stone is the part for which the almond is cultivated and is most variable, the chief differences being that some have thick hard shells and others thin soft shells.

The leaves of plums are convolute, or rolled up, in the bud. Cherry, peach and almond leaves are conduplicate, that is are folded lengthwise along the midrib in bud while the leaves of the apricot, like those of the plum, are convolute. The manner in which the leaves are packed in the bud is a fine mark of distinction in stone-fruits. In size and shape of leaves, as well as in the finer marks of these organs, the botanist and pomologist find much to aid in distinguishing species and varieties but little that holds in separating the sub-genera. The last statement holds true with the floral organs also.

The near affinity of the stone-fruits is further shown by the fact that plums and apricots, plums and cherries, and the several species of each of the distinct fruits inter-hybridize without much difficulty. It is a fact well-known that hybrids often surpass their parents in vigor of plant and in productiveness and this has proved true with most of the hybrids in Prunus of which we have accounts, thereby giving promise of improved forms of these plants through hybridizing. The great variation in wild and cultivated native plums is possibly due to more or less remote hybridity.

Prunus is a most variable genus. This is indicated by the several sub-genera, the large number of species and the various arrangements of these groups by different authors. At their extremes sub-genera and species are very distinct, but outside of the normal types, and sometimes in several directions, there are often outstanding forms which establish well-graded connections with neighboring groups. For example, among the American plums there are but few species between which and some other there are not intermediate forms that make the two species difficult to distinguish under some conditions. There is also a wide range of variation within the species. The modifications within the species are oftentimes such as to change greatly the aspect of the plant; the trees may be dwarf or luxuriant, smooth or pubescent; may differ in branching habit, in leaf-form, in size and color of the flowers, in the time of opening of leaf and flower-buds, in color, shape, size, flesh, flavor and time of ripening of fruit, in the stone and in all such characters as climate and soil environment would be liable to modify.

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This inherent variability is one of the strong assets of the genus as a cultivated group of plants, for it allows not only a great number of kinds of fruits and of species but a great number of varieties. Besides, it gives to the genus great adaptiveness to cultural environment, in accordance with climate, location, soil and the handling of the trees. The cultivator is able to modify, too, the characters of members of the genus to a high degree in the production of new forms, but few, if any, groups of plants having produced as many cultivated varieties as Prunus.

The genus Prunus is preeminent in horticulture, furnishing all of the so-called stone-fruits, fruits which for variety, delicious flavor and beauty of appearance, probably surpass those of any other genus, and which, fresh or dried, are most valuable human foods. The seeds of one of the fruits belonging to Prunus, the almond, are commercially important, both for direct consumption and for the oil which is pressed from them; in India a similar oil is obtained from the seeds of peaches and apricots, while in Europe an oil from the seeds of the Mahaleb cherry is used in making perfumes. Various cordials are made from the fruits of the several species, as kirschwasser and maraschino from cherries, zwetschenwasser and raki from plums, and peach brandy from the peach; while fruits and seeds of the several species are soaked in spirits for food, drink and medicinal purposes. The bitter astringent bark and leaves are more or less used in medicine as is also the gum secreted from the trunks of nearly all the species and which, known as cerisin, is used in various trades. The wood of all of the arborescent species is more or less valuable for lumber, for cabinet-making and other domestic purposes.

Prunus is prolific also in ornamental plants, having in common to recommend them, rapidity of growth, ease of culture, comparative freedom from pests, and great adaptability to soils and climates. The plants of this genus are valued as ornamentals both for their flowers and for their foliage. Many cultivated forms of several of the species have single or double flowers, or variegated, colored or otherwise abnormal leaves, while the genus is enlivened by the evergreen foliage of the cherry laurels. Nearly all of the plants of Prunus are spring-flowering but most of them are attractive later on in the foliage and many of them are very ornamental in fruit.

PLUMS.

Of all the stone-fruits plums furnish the greatest diversity of kinds. Varieties to the number of two thousand, from fifteen species, are now[5] or have been under cultivation. These varieties give a greater range of flavor, aroma, texture, color, form and size, the qualities which gratify the senses and make fruits desirable, than any other of our orchard fruits. The trees, too, are diverse in structure, some of the plums being shrub-like plants with slender branches, while others are true trees with stout trunks and sturdy branches; some species have thin, delicate leaves and others coarse, heavy foliage. In geographical distribution both the wild and the cultivated plum encircle the globe in the North Temperate Zone, and the cultivated varieties are common inhabitants of the southern temperate region, the various plums being adapted to great differences in temperature, moisture and soil in the two zones.

The great variety of plums and the variability of the kinds, seemingly plastic in all characters, the general distribution of the fruit throughout the zone in which is carried on the greatest part of the world’s agriculture, and the adaptation of the several species and the many varieties, to topographical, soil and climatic changes, make this fruit not only one of much present importance but also one of great capacity for further development. Of the plums of the Old World the Domesticas, Insititias and probably the Trifloras have been cultivated for two thousand years or more, while the work of domesticating the wild species of America was only begun in the middle of the last century. There are about fifteen hundred varieties of the Old World plums listed in this work, and since the New World plums are quite as variable, as great a variety or greater, since there are more species, may be expected in America.

An attempt is made in The Plums of New York to review the plum flora of this continent, but the species considered fall far short of being all of the promising indigenous plums; not only are there more to be described, but it is probable that species here described will in some cases be sub-divided. The development of the pomological plum-wealth of North America is but begun. Not nearly as much has been done to develop the possibilities of the European plums in America as in the case of the other tree-fruits. Probably a greater percentage of the varieties of Old World plums commonly cultivated came from across the sea, than of the varieties of any other of the orchard-fruits which have been introduced. Much remains to be done in securing greater adaptability of foreign plums to American conditions. Native and foreign plums are also being hybridized with very great advantage to pomology.

The Plums of New York is written largely with the aim of furthering the development of plums in America, the possibilities of which are indicated[6] in the preceding paragraph. With this end in view the first task is to name and discuss briefly the characters of plums whereby species and varieties are distinguished, with a statement, so far as present knowledge permits, of the variability of the different characters. It is absolutely essential that the plum-grower have knowledge, especially if he aspires to improve the fruit by breeding, of the characters of the plants with which he is to work. These are in the main as follows:

All species and some horticultural varieties have more or less characteristic trees. Making due allowance for environment—food, moisture and light—many plum groups can be readily distinguished by the general aspect of the plant. Of the gross characters of trees, size is usually most characteristic. A species, for example, is either shrubby or tree-like. Yet under varying environment, size of plant and of the parts of the plant, are probably the first to change. Habit of growth is nearly as important as size and varies but little under changing conditions. A species or variety may be upright, spreading, drooping or round-topped in growth; head open or dense; the tree rapid or slow-growing. Hardiness is a very important diagnostic character, plums being either hardy, half-hardy or tender. Both species and varieties respond in high degree to the test of hardiness, the range for varieties, of course, falling within that of the species. Productiveness, regularity of bearing, susceptibility to diseases and insects, and longevity of tree are all characters having value for species and varieties and with the exception of the first named, are little subject to variation.

The thickness, smoothness, color and manner of exfoliation of the outer bark and the color of the inner bark have considerable value in determining species but are little used in determining horticultural groups. It is well recognized that all plums have lighter colored bark in the South than in the North. The branches are very characteristic in several species. The length, thickness and rigidity of the branch and the length of its internodes should be considered, while the direction of the branch, whether straight or zigzag, are very valuable determining characters and relatively stable ones, seeming to change for most part only through long ranges of climatic conditions. So, too, the arming of a branch with spines or spurs and the structure of such organs are important. The color, smoothness, amount of pubescence, direction, length, thickness and the appearance of the lenticels, the presence of excrescences on the branchlets of the first and second year’s growth and the branching angle, are all worthy[7] of consideration though quite too much has been made of these characters, especially of pubescence, in determining species, for they are all extremely variable.

1. P. HORTULANA MINERI 2. P. AMERICANA 3. P. CERASIFERA

4. P. DOMESTICA 5. P. INSITITIA 6. P. HORTULANA

7. P. MUNSONIANA 8. P. NIGRA 9. P. TRIFLORA

The size, shape and color of leaf-buds and of their outer and inner scales and the margins of the scales differ in different species. Possibly the most evident, and therefore readiest means of identifying species, at least, is by the leaves. It is true that leaves are very variable but always within limits, and either individually or collectively in giving the general aspect to a tree they are characteristic. Modifications of leaves most often occur in very young plants, those growing in bright sunshine or deep shade and on sprouts or suckers, but none of these are usually sufficient to mislead as to species. Leaf-size and leaf-form are the first characters to be noted in determining a plum but these are closely followed in value by leaf-color, leaf-surface, leaf-thickness and leaf-margin. Leaf-size is variable, depending much upon the conditions noted above but leaf-form varies but little in the several species. So, too, the color of leaves is very constant throughout a species, for both surfaces, though impossible to describe accurately in words and very difficult to reproduce in color-printing. There is a marked difference in autumnal tints not only of species but of varieties but these are not very constant in any one location and must vary greatly under different environments. The thickness of the leaves of the several species is a distinctive character. Species of plums have very different leaf-surfaces as regards reticulation, rugoseness, pubescence and coriaceousness, all of these characters being quite constant, though it is to be noted that roughness of leaves and pubescence are increased by exposure to the sun and by the influence of some soils. There is, indeed, considerable variation in the pubescence of the leaves of all species of plums in different parts of the country and probably too much has been made of pubescence as a determining character.

The margins of leaves are very characteristic of species and scarcely vary under normal conditions if the teeth at the middle of the sides be taken rather than those toward the base or apex, these very often being crowded, reduced or wanting. The presence of glands, their position, size, shape and color, help to characterize several species and seem to be fairly constant guides. Some species and a great number of varieties have the distinguishing marks of gland-like prickles tipping the serrations in the leaf-margins. Length, thickness, rigidity and pubescence of petiole have some taxonomic value. Stipules usually offer no distinguishing marks other than those mentioned under leaves.

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The blossoms of plums are very characteristic, giving in flowering time a distinctive aspect to all species and distinguishing some horticultural varieties. The flowers of all the species are borne in clusters, differing in number of individuals, according to the species; so, too, the flowers in the different species vary in size, color, in length of their peduncles, and in pubescence, especially of the calyx. Flower-characters are constant, taking them as a whole, yet there are some variations that must be noted. One of the most marked of these is in the time of appearance of the flowers; in the South they appear before the leaves but in the North with the leaves. On the grounds of this Station there are notable exceptions to the latter statement, with varieties of species showing considerable variation in this regard. There are some remarkable variations within species as regards size and color of the corolla and glands and pubescence of the calyx, depending upon the environment of the plant; but on the whole these characters are very constant. The fragrance of the flowers of plums varies from a delicate, agreeable odor to one that is quite disagreeable in some species as in Americana; the odor seems to be a constant character.

Of all structures of the plum the fruit is most variable, yet fruits are sufficiently distinct and constant, especially within species, to make their characters very valuable in classification. Species, whether wild or cultivated, may be distinguished in greater or less degree by the period of ripening of the fruits, though in this regard the cultivated varieties of the several species vary greatly and in the wild state trees of native plums in the same locality, even in the same clump, may vary in ripening as much as from two to four weeks. Species are distinguished by size, shape, color, flesh, flavor and pit among the grosser characters of the structure and by amount of bloom, stem, cavity, apex, suture and skin among the minor characters. The fruit is usually the first part of the plant to respond to changed conditions.

Characters derived from seed structures are generally accounted of much value by botanists in determining species. Such is the case with plums. This Station has a collection of stones of over three hundred cultivated varieties of plums and some specimens of nearly all the different species. The stones illustrated in the color-plates in this book show that this structure is quite variable in size, shape, in the ends, surfaces, grooves and ridges, even within a species; nevertheless in describing the several hundred forms of plums for The Plums of New York the stone has been quite as satisfactory, if not the most satisfactory, of any of the organs of this plant for distinguishing the various species and varieties.

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The reproductive organs of plums afford several characters and would seem to offer means of distinguishing botanical and horticultural groups, but they are so variable in both cultivated and wild plants as to be very misleading. Not only do these organs differ very often in structure but also in ability to perform their functions. Bailey[1] has called attention to the remarkable self-sterility of some varieties of the native species of plums, due to the impotency of the pollen upon flowers of the same variety. C. W. H. Heideman[2] made some very interesting observations on what he considers distinct forms of the flowers of the Americana plums, describing for this species all of the six possible variations of flowers enumerated by Darwin in his Different Forms of Flowers in Plants of the Same Species. Heideman thinks that other species of Prunus exhibit similar variations. Waugh[3] made the pollination of plums a subject of careful and extended study and found much variation in the pistils of plants of the same species, insufficient pollen in some plants, pollen impotent on the stigma of the same flower, and considerable difference in the time of maturity of pollen and stigma in some plums, especially the Americana plums. These variations, most important to the plum-grower, are of more or less use in identifying plums.

After the discussion of the characters of plums we may pass to a detailed description and discussion of the species of plums which now contribute or may contribute cultivated forms to the pomology of the country either for their fruits or as stocks upon which to grow other plums. The following conspectus shows as well as may be the relations of the species of plums to each other.

CONSPECTUS OF SPECIES OF PLUMS.

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1. PRUNUS DOMESTICA Linnaeus

Beside the comparatively well-known groups of Domestica varieties, there are in Europe, with an occasional representative in America, especially in herbaria, numerous other groups either a part of Prunus domestica[13] or possibly, in a few cases at least, hybrids between it and other species. European botanists place some of these in distinct species or sub-species; but few, however, even of the recent writers on the botany of the plum, agree at all closely as to the disposition of these edible and ornamental plums which may be doubtfully referred to Prunus domestica. With this disagreement between the best European authorities where these plums have long been known, where some of them have originated, and all may be found in orchards, botanic gardens and herbaria, it does not seem wise at this distance to attempt a discussion of such doubtful forms. It is certain, however, that Borkhausen’s Prunus italica and Prunus œconomica, as given in the synonymy, are but parts of Prunus domestica, the first including the Reine Claude plums and the latter the various prunes. So, too, a wild form named by Borkhausen, Prunus sylvestris, is probably a part of Prunus domestica.

Bechstein[4] gave specific names to a number of plums which Schneider[5] holds are all cultivated forms of Prunus domestica. These names are not infrequently found in botanical and pomological literature, to the great confusion of plum nomenclature. The following are Bechstein’s species:—Prunus exigua, Prunus rubella, Prunus lutea, Prunus oxycarpa, Prunus subrotunda and Prunus vinaria.

The plum in which the world is chiefly interested is the Old World Prunus domestica. The Domestica plums are not only the best known of the cultivated plums, having been cultivated longest and being most widely distributed, but they far surpass all other species, both in the quality of the product and in the characters which make a tree a desirable orchard plant. How much of this superiority is due to the greater efforts of man in domesticating the species cannot be said, for the natural history of this plum, whether wild or under cultivation, is but poorly known. It is not even certain that these plums constitute a distinct species, there being several hypotheses as to the origin of the Domestica varieties. Three of these suppositions must be considered.

Many botanists hold that what American pomologists call the species is an assemblage of several botanical divisions. The early botanists distributed these plums in botanical varieties of one species. Thus Linnaeus, in 1753, divided Prunus domestica into fourteen sub-species, and Seringe, in 1825, made eight divisions of the species. Both of these men include[14] in this species, among others, plums which we now place in Prunus cerasifera, the Cherry plums, and Prunus insititia, the Damsons and Bullaces. Nearly all subsequent botanists who have not made two or more species of it have recognized from two to several sub-divisions of Prunus domestica. It is possible that what are called the Domestica plums should be distributed among several botanical divisions. But it is difficult to find any differential character sufficiently constant to distinguish more than one species for the several hundred varieties of these plums now under cultivation. Nor are there any cleavage lines sufficiently distinct to indicate that the edible varieties of the one species should be sub-grouped.

In coming to these conclusions the writer has studied about three hundred varieties of Domestica plums growing on the grounds of this Station and about half as many more growing in other parts of the country, the whole number representing all of the various species and sub-species which other workers have made. The differences which have been most used to classify the varieties of Domestica in several botanic divisions have to do chiefly with the fruit, as size, shape, color and flavor, characters so modified by cultivation and selection that they are artificial and transitory and of little value in botanical classification. Moreover, the botanical groups which have been founded on these characters are much more indistinct than ordinarily in botany because of the merging at many points of one group into another. This indistinctness is greatly increasing year by year through the intercrossing of varieties. When the characters of no value to man, and, therefore, little modified by cultivation, are considered, it is scarcely possible logically to place Domestica plums in more than one species or to further sub-divide the one species.

The botanists who have divided the Domestica plums into either greater or lesser botanical groups do not define their divisions with sufficient accuracy to make them clearly recognizable. Neither do they give the habitats of the wild progenitors with sufficient certainty to carry conviction that the groups were brought under cultivation from separate ancestors. Also, the several botanists who hold to the multiple species theory for the Domestica plums do not agree as to the limits of the different groups and give to them very different specific or variety names, showing that they have widely different ideas as a basis for their classification.

A second theory is that Prunus domestica is derived from Prunus spinosa and that Prunus insititia is an intermediate between the two.[6][15] This hypothesis is based upon the supposition that when Domestica plums run wild they revert to the Insititia or Spinosa form. It is not difficult to test this theory. A study of the origin of the several hundred Domestica and Insititia plums discussed in Chapters III and IV of The Plums of New York does not show for any one of them a tendency to reversion or evolution to other species; nor do the descriptions indicate that there are many, if any, transitional forms. During the two thousand years they have been cultivated in Europe the Old World plums have been constant to type. Domestica seedlings vary somewhat but they do not depart greatly from a well marked type. Such very few striking departures as there seem to be are more likely to have arisen through crossing with other species than through reversion or evolution. This Station has grown many pure seedlings or crosses of varieties of Domestica within the species and has had opportunity of examining many more from other parts of the State, and none of these show reversion to the other two Old World species. Nor, as we shall see, is there much in what is known of the history of these three species to lead to the belief that the Domestica, Insititia and Spinosa plums constitute but one wild species or have arisen from one.

It has been remarked that there are few, if any, transitional forms between the Domestica and other European plums. It is a significant fact that Prunus domestica can be hybridized with other species of plums only with comparative difficulty, species of plums as a rule hybridizing very freely. This is as true with the Insititia and Spinosa as of other plums, there being few recorded hybrids of either of these species with the one under discussion. Quite to the contrary the varieties of the several pomological groups of Domestica plums hybridize very freely. If all were of one species we should expect many hybrids between the Domestica, Insititia and Spinosa plums.

We are now left with the third hypothesis, which is, as we have indicated in a preceding paragraph, that the varieties of Domestica plums belong to one species; or if they have come from more than one species the wild forms have not been distinguished and must have grown under much more nearly similar conditions than is the case with Prunus domestica and any other species. Without knowledge of more than one wild form, and in view of the intercrossing of the varieties of these plums it seems best to consider all as parts of one species, leaving to the pomologist the division of the species into horticultural groups founded on the characters which make the fruit valuable for cultivation.

[16]

Assuming, then, that the plums known in pomology as Domestica plums belong to one species, the original habitat of the species may be sought. In spite of the great number of varieties of plums now grown in Europe and western Asia, and the importance of the fruit both in the green and dried state, the history of the plums cannot be traced with much certainty beyond two thousand years. Though stones, without doubt those of the Insititia or Damson and the Spinosa or Blackthorn plums, are found in the remains of the lake dwellings in central Europe[7] the pits of Domestica plums have not yet come to light. In the summer of 1909 the writer, in visiting historic Pompeii, became interested in the illustrations of fruits in the frescoes of the ancient buildings, but neither in the houses of the ruined city nor in the frescoes in the museums in Naples could he find plums, though several other fruits, as apples, pears, figs and grapes were many times illustrated. An examination of the remains of plants preserved in the museum at Naples taken from under the ashes and pumice covering Pompeii gave the same results. No stone-fruits were to be found, though if widely used these should have been on sale in the markets of Pompeii at the time of the destruction of the city, which occurred late in August,—the very time of the year at which the examination was made and at which time plums were everywhere for sale in Rome. This observation is but another indication that plums were not well-known before the beginning of Christianity, since Pompeii was destroyed in 79 A. D. In Greek literature the references to plums are few before the Christian era and these are more likely to some form of Insititia, as the Damsons, rather than to the Domesticas.

While the records are somewhat vague it is probable that the Domestica plums came from the region about the Caucasus Mountains and the Caspian Sea and especially the section east of these mountains and the sea. What seems to be the wild form of this species has been found by several botanists in this great region.[9] Here the Huns, Turks, Mongols and Tartars, flowing back and forth in tides of war-like migration, maintained in times of peace a crude agriculture probably long before the Greeks and Romans tilled the soil. The plum was one of their fruits and the dried prune a staple product. Here, still, to the east, west and north toward central Asia, plums are among the common fruits and prunes are common articles of trade. Even in the fertile oases of the great central Asian desert, plums are cultivated, but whether domesticated here or brought from elsewhere cannot be told. Koch,[10] speaking of prunes in particular, gives the following account (translated) of their Asiatic origin:

At about the time Pliny wrote, or somewhat before, communication had been opened between the Romans and the countries about the Caspian Sea, and a few centuries later the devastating hordes of Asiatics came westward and for several centuries continued to pour into eastern Europe. What more probable than that they should have carried dried prunes as an article of food in the invasions, and eventually, as they made settlements here and there, have introduced the trees in Europe. It is certain, at any rate, as we shall see, that several of the groups of cultivated plums trace back to the Balkan countries of Europe and the region eastward. There, now as then, the plum is a standard fruit and prune-making a great industry.

The plum when first known in Europe, as described by Pliny and other early writers, seems to have been a large and well-flavored fruit, indicating that it had been under cultivation for a long while. This, and the fact that the fruit was not known by the earliest writers on agriculture, indicate that the plum was not originally an inhabitant of southern Europe, as some suppose. It is likely that the tree has escaped from cultivation and become naturalized in the localities where it is now supposed to grow wild. Prunus domestica has not been found wild nor under cultivation in eastern Asia, so far as can be learned by the botanical and horticultural explorers of China and nearby regions, Prunus triflora being the domesticated plum of that part of the continent, though it may well be surmised that some of the Domestica plums are cultivated in western China, a region as yet but imperfectly explored for its plants.

Having briefly sketched the origin of the Domestica plums in the Old World we may now consider their history in the New World—a more satisfactory task, as data are abundant and reliable.

The Domestica plums are valuable food-producing trees in America but have not attained here the relative importance among fruits that they hold in Europe. From the earliest records of fruit-growing in the New World the plum has been grown less than the apple, pear, peach or cherry, while in Europe it is a question if it does not rank first or second among the tree-fruits. The comparatively restricted area which the[19] Domestica plums now occupy in America is due, perhaps, to the fact that they do not possess in as high degree as the fruits named above the power of adaptation to the trans-Atlantic environment. Without question the feature of environment most uncongenial to plums in America is the climate. The plum thrives best in an equable climate like that of eastern and southern Europe and of western America, and cannot endure such extremes of heat and cold, wet and dry, as are found in parts of eastern America and in the Mississippi Valley. At best this fruit lacks in what is called constitution, or ability to withstand adverse conditions of any kind, whether of climate, culture, insects or fungi. Thus in America this plum suffers severely not only from climate but from several parasites, as curculio, black-knot, leaf-blight, plum-pockets and other pests.

We find, therefore, that in North America the Domestica plums are confined to favored localities on the Atlantic seaboard, the Great Lakes region and the Pacific coast. In the first named area they are to be found thriving to a limited degree in Nova Scotia and parts of Quebec, somewhat in central New England, and particularly well in the fruit-growing sections of New York, especially in the parts of this State where the climate is made equable by large bodies of water. South of New York, excepting in a few localities in Pennsylvania, but few plums of this species are grown. The Domestica plums are grown with indifferent success in southern Ontario and in Michigan, and now and then an orchard is found to the south almost to the Gulf. In the great Valley of the Mississippi and in the states of the plains this plum is hardly known. Westward in the irrigated valleys of the Rocky Mountains and the Great Basin, the climate is favorable and the European plums are nearly as well-known as in any other portion of the continent excepting the Pacific Coast.

It is in the last named region that the foreign plum reaches its highest development in the New World. The trees in California, Oregon and Washington are very thrifty and the plums are of large size, handsome appearance and of high quality. Both tree and fruit in this favored region are free from most of the insect and fungus troubles with which the eastern plum-growers must contend. Curculio and black-knot, scourges of eastern orchards, are not troublesome on the western coast. In this region the Domesticas, practically the only plums cultivated, succeed on either irrigated or naturally watered lands.

It is probable that some of these plums were introduced into America by the first colonists, but if so, the early records do not show that the fruit[20] was much grown in this country until toward the end of the Eighteenth Century. Certainly during the first two centuries of colonization in the New World there were no such plum plantations as there were of the apple, pear and cherry. Among the first importations of plums were those made by the French in Canada, more particularly in Nova Scotia, Cape Breton, Prince Edward Island and in favored situations such as the L’Islet County and the Island of Montreal bordering and in the St. Lawrence River.

Peter Kalm in his Travels into North America in 1771 records the culture of plums as far north as Quebec with the statement that “Plum trees of different sorts brought over from France succeed very well here,” adding further, “The winters do not hurt them.”[11] There are other records to show that the French, always distinguished for their horticultural tastes, if not the first to grow this fruit in America, at least began its culture at a very early date.

In the voyages undertaken for exploration and commerce soon after the discovery of America by Columbus the peach was introduced in America by the Spanish; for soon after permanent settlement had been made in the South the settlers found this fruit in widespread cultivation by the Indians and its origin could only be traced to the Spaniards who early visited Florida and the Gulf region. William Penn wrote as early as 1683 that there were very good peaches in Pennsylvania; “not an Indian plantation was without them.”[12] The abundance of this fruit was noted by all the early travelers in the region from Pennsylvania southward and westward but though the wild plums are often mentioned there are no records of cultivated plums until the colonies had long been established.

In Massachusetts some plums were planted by the Pilgrims, for Francis Higginson, writing in 1629, says: “Our Governor hath already planted a vineyard with great hope of increase. Also mulberries, plums, raspberries, corrance, chestnuts, filberts, walnuts, smalnuts, hurtleberries.”[13] The plums were Damsons, as a statement is made a little later that the “Red Kentish is the only cherry and the Damson the only plum cultivated.” A further reference to this plum is made by John Josselyn, when, writing of a voyage to New England in 1663, he says, “The Quinces, Cherries, Damsons,[21] set the dames a work, marmalad and preserved Damsons is to be met with in every house.”[14]

In 1797 there is the following concise account of the plums cultivated in New England:[15]

A search in the colonial records of Pennsylvania, New Jersey and Delaware shows no records of cultivated plums in these states until the establishment of the Bartram Botanic Garden near Philadelphia in 1728. Here John Bartram grew fruits, trees and flowers of many kinds received through exchanges of indigenous species with European correspondents. Among the plants sent over from Europe to Bartram were several varieties of plums which were propagated and distributed throughout Pennsylvania and nearby provinces. It must not be supposed, however, that the Domestica plums had not been grown in Pennsylvania previous to Bartram’s time. The plum grows fairly well in localities of this region, and without question it had been planted by the early colonists with seeds brought from across the sea. But the absence of references to the plum, where they abound to the apple, pear, peach, quince and cherry, shows that this fruit was not much cultivated by the Quakers and Swedes who settled in the three states watered by the Delaware.

In the southern colonies the Domestica plums grow but poorly, and as the early settlers of these states were chiefly concerned with tobacco and cotton, paying little attention to fruits, we should expect the plum to have been neglected. Then, too, the peach, escaped from the early Spanish settlements, grew spontaneously in many parts of the South, furnishing, with the wild plums of the region, an abundant supply of stone-fruits. Yet the plum was early introduced in several of the southern colonies.

Thus Beverly,[16] writing in 1722 of Virginia, says: “Peaches, Nectarines and Apricocks, as well as plums and cherries, grow there upon standard[22] trees,” with the further statement that these fruits grew so exceedingly well that there was no need of grafting or inoculating them. Lawson,[17] in his history of North Carolina, written in 1714, says that the Damson, Damazeen and a large, round, black plum were the only sorts of this fruit grown in that state in 1714.

In South Carolina Henry Laurens, who should be accounted a benefactor not only of that State but of the whole country as well, about the middle of the Eighteenth Century grew in Laurens Square in the Town of Amonborough all the plants suitable to that climate that widely extended merchantile connections enabled him to procure. Thus among fruits he grew olives, limes, Alpine strawberries, European raspberries and grapes, apples, pears and plums. John Watson, one of Laurens’ gardeners, planted the first nursery in South Carolina. His plantation was laid waste in the Revolution, though it was afterwards revived by himself and his descendants and was still further continued by Robert Squib. The plum in several varieties was largely grown and distributed from this nursery.

Charleston, South Carolina, was at the beginning of the Nineteenth Century the southern center of horticultural activities and the European plum was widely distributed from here at this time. Of the several botanic gardens, really nurseries, in Charleston, one was conducted by André Michaux who was sent by the French Government in 1786 to collect American plants. Another was owned by John Champneys at St. Pauls, near Charleston, and was managed by a Mr. Williamson who grew all of the species of trees, fruits and shrubs, native and foreign, which could be procured.[18] The third of these gardens was owned by Charles Drayton at St. Andrews in which not only exotic fruits were grown but those of the region as well. The plum trees frequently mentioned in the records of the time as growing in this region came from these nurseries.

In Florida, as has been stated, the peach was introduced by the Spanish explorers, but if the plum were also planted by the Spaniards it quickly passed out with the cessation of cultivation. But later there are records[19] of this and nearly all of the fruits of temperate and sub-tropic climates having been grown at St. Augustine and Pensacola. In the remarkable colony[20] founded by Dr. Andrew Turnbull at New Smyrna, Florida, in[23] 1763, the plum was one of the fruits cultivated. It is not probable, however, that the culture of this fruit was ever extensive in Florida as it does not thrive there.

William Bartram, son of John Bartram the founder of the Bartram Botanic Garden, set out on a botanical expedition through the Southern States in 1773, which lasted five years. He records[21] numerous observations on the horticulture of both the colonists and the Indians. At Savannah, Georgia, he found gardens furnished with all the cultivated fruit trees and flowers in variety. One of the earliest settlements made by the English in Georgia was Frederica, and here he found the peach, fig, pomegranate and other trees and shrubs growing about the ruins; though not specifically mentioned, the plum had probably been planted here with the other fruits. At the junction of the Coose and Tallapoosa rivers in Alabama, there were thriving apple trees, which had been set by the French at Pearl Island in the last named state. Between Mobile and New Orleans, Bartram found peaches, figs, grapes, plums and other fruits growing to a high degree of perfection and such also was the case on a plantation on the Mississippi in Louisiana near Baton Rouge.

These several references to plums show that this fruit was at least tried in early colonial times, but it was not until after the establishment of fruit-growing as an industry that any extensive plantings were made. Pomology really began in America, though it languished for the first half-century, at Flushing, Long Island, about 1730 with the establishment of a commercial nursery by Robert Prince, first of four proprietors. Just when this nursery, afterwards the famous Linnaean Botanic Garden, began to offer plums cannot be said, but in 1767 one of their advertisements shows that they were selling plum trees. As a possible indication that the fruit was not highly esteemed at this period, an advertisement of trees for sale from this nursery in the New York Mercury of March 14th, 1774, does not offer plums. But in 1794 the catalog of the nursery offers plums in variety. Indeed, as we shall see, William Prince had at this time taken hold of the propagation and improvement of the Domestica plums with great earnestness.

William Prince, third proprietor of the nursery founded by his grandfather says in his Treatise of Horticulture,[22] “that his father, about the[24] year 1790 planted the pits of twenty-five quarts of Green Gage plums; these produced trees yielding fruit of every color; and the White Gage [Prince’s Imperial Gage], Red Gage and Prince’s Gage, now so well known, form part of the progeny of these plums, and there seems strong presumptive evidence to suppose that the Washington Plum was one of the same collection.” In 1828 the Prince nursery was offering for sale one hundred and forty varieties of plums which William Prince states[23] “are a selection only of the choicest kinds, in making which, the commoner fruits have been altogether rejected.” Of the kinds grown, there were over twenty thousand trees.[24] To this nursery, to William Prince and to William Robert Prince,[25] the fourth proprietor in particular, belong the credit of having given plum-growing its greatest impetus in America.

Other notable nurseries founded at the close of the Eighteenth Century, which helped to establish plum culture in America, were those of the Kenricks, of William Coxe, and of David Landreth and Son. The Kenrick Nursery was founded in 1790 at Newton, Massachusetts, by John Kenrick, under whom and his sons, William and John A., the business was continued until 1870.[26] During a large part of this period the Kenrick Nursery probably grew, imported and disposed of a greater quantity of fruit trees than any other nursery in New England. Coxe’s nursery was established in 1806, at Burlington, New Jersey, but he had been growing fruit for many years previous and was thus a pioneer pomologist before[25] becoming a nurseryman. In his book, A View of the Cultivation of Fruit Trees, published in 1817, the first American book on pomology, he says[27] he had been “for many years actively engaged in the rearing, planting and cultivating of fruit trees on a scale more extensive than has been attempted by any other individual of this country.” The third of these nurseries, that of David Landreth and Son, was conducted in connection with the seed establishment of that family founded in Philadelphia in 1784. Their collection of fruits was among the most extensive of the time and must have forwarded the cultivation of the plum in that region.[28]

A century ago the fruit-growing of the country was largely in the hands of amateurs and patrons of horticulture. Many varieties of plums must have been introduced by these lovers of plants. Among such growers of fruit was William Hamilton of Philadelphia, who introduced the Lombardy poplar in 1784, and who in 1800 was growing all the plants and fruits procurable in Europe. Ezekiel Henry Derby of Salem, Massachusetts, one of the founders of the Massachusetts Society for Promoting Agriculture, grew many choice foreign plants in his garden, greenhouse, orchard and arboretum, and attained well merited fame as a horticulturist.[29] Dr. David Hosack, botanist and founder in 1801 of the Elgin Botanic Gardens in what is now New York City, was one of the most distinguished patrons of pomology of his time and grew many new fruits and plants from Europe, afterwards placing them in the hands of the horticulturists of the country.[30]

These are but a very few of the many men who, having wealth and leisure, were engaged in growing fruits and plants as an avocation but were adding greatly to the material and knowledge of those to whom fruit-growing was a vocation. As a further example of how much these men contributed to horticulture, a purchase made by a member of the New York Horticultural Society may be cited. At a meeting of the Society held in July, 1822, he mentioned a list of fruit trees which he had purchased in Europe, comprising 784 varieties.[31]

The period during which American pomology may be said to have been in the hands of wealthy amateurs began shortly after the close of the Revolution and did not fully merge into that of commercial pomology until the close of the Civil War. Soon after the beginning of the Nineteenth[26] Century, horticulture, in fact all agriculture, was greatly stimulated by the publication of agricultural books[32] and magazines[33] and the formation of agricultural and horticultural societies.[34] The frequency of the names of these publications of a century ago in The Plums of New York is an indication of the contributions they made to the culture of the plum.

Having briefly outlined the history of the Domestica plums, we come now to a discussion of what we have under cultivation in this fruit. The Domestica plums, 950 or more mentioned in this text, may be divided into several more or less distinct pomological groups. These groups are of interest because in their history the evolution of the plum under consideration is further developed; because such groups are serviceable to plum-growers, as each division has adaptation for particular conditions or particular purposes; and because of their value to the breeder of plums since the largest and best differentiated groups, as a rule, have their characters most strongly fixed and may be relied upon to best transmit them to their offspring.

Groups of plums in pomology are founded for most part upon the characters of the fruit since these are most readily recognized by fruit-growers. Yet whenever possible, leaf, flower and tree-characters are considered. The name given is usually that of the best known variety in the group though in some of the divisions the name is that of the variety which seems to be intermediate in character between the other members of the group.

The groups of plums recognized by pomologists were far more distinct as we go back in their history. For, in the past, each fruit-growing region[27] had a pomology of its own in which the varieties of any fruit were few and similar, constituting but one, or at most a very few types. The various groups of plums, therefore, largely represent distinct plum-growing regions. With the increase in intercourse between the countries of the world, cultivated plums have been taken from place to place and as new varieties have originated, often from crosses between varieties, the dividing lines between divisions have been more or less broken down. The first of the groups to be considered is:—

The Reine Claude or Green Gage Plums.—This group is so distinctive in several characters that some botanists and pomologists separate it from other Domestica plums as a sub-species or species[35] and in common parlance its numerous varieties are very generally grouped together as “green gages” as if it were quite a distinct fruit from other plums. It comprises a considerable number of relatively small, round, mostly green or golden plums of so high quality as to make them standards in this respect for all plums. The Reine Claude is one of the oldest types of which there are records. Its varieties reproduce themselves without much variation from seed though there are a few sorts, possibly crosses with some other group, which are doubtfully referred to the Reine Claudes. The later history of these plums is most interesting and is reliable, for the group is recognized and discussed by almost every European or American pomologist who has written in three centuries.[36] The early history is not so well known.

Where the Reine Claude plums originated no one knows. Koch[37] says he has eaten wild plums in the Trans-Caucasian region, which must be recorded with the Reine Claudes, but on the next page he advances the theory that the group is a hybrid between Prunus domestica and Prunus insititia. Schneider[38] puts the Reine Claudes in Prunus insititia. The group seems to be a connecting link between the two species named above, having so many characters in common with each that it is exceedingly difficult to choose between the two as possible parent species. Prunus domestica probably originated in the Caucasian or Caspian region, and it is likely, as Koch suggests, that the Reine Claudes were brought from there. This is substantiated by the early pomologists, who say these[28] plums came originally from Armenia and were known as the Armenian plums, coming eventually by the way of Greece to Italy. If this statement of its origin be true, Columella[39] knew the fruit, for he says:

And so, too, Pliny refers to them[40] in his enumeration of varieties in which he says: “the Armenian, also an exotic from foreign parts, the only one among the plums that recommends itself by its smell.”

Hogg[41] says the Reine Claudes were brought from Greece to Italy and cultivated in the latter country under the name Verdochia. Hogg does not give his authority and his statement cannot be verified in any other of the modern European pomologies to which the authors of this work have had access. The very complete history of the agricultural and horticultural plants of Italy[42] by Dr. Antonio Targioni-Tozzetti does not give this name. Be that as it may, some variety of this group was introduced into England under the name Verdoch and at an early date, for in 1629 Parkinson[43] enumerates it in his sixty sorts describing it as “a great, fine, green shining plum fit to preserve.” Rea[44] in 1676 also lists and describes it as does Ray,[45] 1688.

It is doubtful if Parkinson, Ray and Rea had the true Reine Claude, however, for the Verdacchio, according to Gallesio,[46] one of the best Italian authorities, is an obovate-shaped fruit while the Claudia is a round one. Gallesio says the Claudia was cultivated in many places about Genoa under the name Verdacchio rotondo; about Rome and through Modenese, for a long time, as the Mammola; in Piedmont as the Claudia; and in Tuscany as the Susina Regina. Now (1839) he says, “it is known in all Italy under the name Claudia, and has become so common as to be found in abundance in the gardens and in the markets.”

The name Reine Claude, all writers agree, was given in honor of Queen Claude, wife of Francis I, the fruit having been introduced into France[29] during the reign of that monarch which began in 1494 and ended 1547, these dates fixing as accurately as possible the origin of the name. Green Gage, the commonest synonym of either the Reine Claude group or of the variety, comes from the fact that this fruit was introduced into England by the Gage family. Phillips[47] gives the following account of its introduction into England:

Because of the high esteem in which the plums of this group have always been held in England the early English colonists probably brought seeds or plants of the Reine Claudes to America. This supposition is strengthened by the fact that Prince, in his efforts in 1790 to improve plums, chose the “Green Gage,” planting the pits of twenty-five quarts of plums of this variety. McMahon, in his list of thirty varieties of plums, published in 1806, gives the names of at least seven varieties belonging to this group. The varieties of the group first came into America, without doubt, under one of the Green Gage names, but afterwards, probably in the early part of the Nineteenth Century, importations from France brought several varieties under Reine Claude names though the identity of the plums under the two names seems to have been recognized in American pomology from the first.

In appearance the trees of this group are low and the heads well rounded. The bark is dark in color and cracks rather deeply. The shoots are thick and do not lose their pubescence. The leaves are large, broad, more or less wrinkled, coarsely crenate and sometimes doubly serrated, a character not usually found in Domestica plums, and bear from one to four glands. The fruit is spherical or ovoid, green or yellow, sometimes with a faint blush, stems short and pubescent, suture shallow, bloom thin, texture firm, quality of the best, flesh sweet, tender, juicy, stone free or clinging.

The leading varieties of the Reine Claude plums are: Reine Claude, Bavay, Spaulding, Yellow Gage, Washington, McLaughlin, Hand, Peters, Imperial Gage, Jefferson and Bryanston.

[30]

The Prunes.—In western America plum-growers usually speak of any plum that can be cured, without removing the pit, into a firm, long-keeping product as a prune. Such a classification throws all plums with a large percentage of solids, especially of sugar, into this group. But in Europe the term is used to designate a distinct pomological group.[48] Since we have a number of varieties of plums long known as prunes and to which no other term can be nearly so well applied, it seems wise to follow the established European custom of using the term as a group name as well as for a commercial product which is made for most part from these plums.

The prune, as an article of commerce, all writers agree, originated in Hungary in the Sixteenth Century and was at that time a very important trading commodity with Germany, France and southern Europe. If, as Koch surmises (see page 17), the prunes originated in Turkestan or farther east—and the statements of other botanists and writers tend to show that his view is correct—the spread of the varieties of this group westward is readily explained. In the migrations of the Huns, from western Asia to eastern Europe, in the first thousand years of the Christian era, some Magyar or Hun intent on cultivating the soil brought with him the prune-making plums which, finding a congenial home, became the foundation of the prune industry of Hungary in the Sixteenth Century. In subsequent commercial intercourse with western Europe the latter region was enriched by these prune-making plums from Hungary.

In America this group is now by far the most important one commercially, though prunes were not introduced into this country until comparatively recent years. The early lists of plums do not include any of the prunes and even as late as 1806 McMahon only mentions in the thirty varieties given by him but one, “the Prune Plum.” William Prince in 1828 speaks only of the “monstrous prune,”[49] but in such a way as to lead one to believe that neither it, nor any other prune, was then cultivated in America.[50] In 1831 William Robert Prince in his Pomological[31] Manual describes from this group only the German Prune and the “Agen Date,” or Agen. Indeed, it was not until the beginning of the prune industry in California, about 1870, that the varieties of this group began to be at all popular though an attempt was made by the United States Patent Office to start the prune industry on the Atlantic seaboard by the distribution of cions of two prunes in 1854.[51]

The growth of the prune industry on the Pacific Coast is one of the most remarkable industrial phenomena of American agriculture. About 1856, Louis Pellier, a sailor, brought to San Jose, California, cions of the Agen from Agen, France. Some time afterward a larger plum, the Pond, was also imported from France, supposedly from Agen, and to distinguish the two, the first was called Petite Prune, by which name it is now very commonly known in the far west. The first cured prunes from this region were exhibited at the California State Fair in 1863; commercial orchards began to be planted about 1870, and the first shipments of cured prunes were probably made in 1875.[52] In 1880 the output per annum was about 200,000 pounds; in 1900 the yearly capacity was estimated to be about 130,000,000 pounds, valued by the producers at $450,000.[53]

The typical varieties of this group are the Italian, German, Agen, Tragedy, Tennant, Sugar, Giant, Pacific and the Ungarish.

The distinguishing characters of the group are to be found in the fruit, which is usually large, oval, with one side straighter than the other, usually much compressed with a shallow suture, blue or purple, with a heavy bloom, flesh greenish-yellow or golden, firm, quality good, stone free. The trees are various but are usually large, upright and spreading with elliptical leaves having much pubescence on the under surface.

The Perdrigon Plums.—The Perdrigons constitute an old but comparatively unimportant group of plums.[54] The name comes from an old[32] time geographical division of Italy.[55] The Perdrigon plums, especially the varieties having this name, have been grown extensively for two centuries about Brignoles, France, where they are cured and sold as Brignoles prunes. Since they are much grown in what was formerly the province of Touraine, France, they are sometimes called Touraine plums. The early pomological writers, as the Princes, Kenrick, Coxe, and even Downing, described White, Red, Violet, Early and Norman Perdrigon plums, but these are not now listed in either the pomologies or the nurserymen’s catalogs of this country though the group is represented by Goliath, Late Orleans and Royal Tours. These plums might almost be included with the Imperatrice group, differing only in the smaller and rounder fruits.

The Yellow Egg Plums.[56]—There are but few varieties belonging to this group, but these are very distinct, and include some of the largest and handsomest plums. The origin of varieties of this group can be traced back over three centuries and it is somewhat remarkable that the size and beauty of the Yellow Egg Plums have not tempted growers during this time to produce a greater number of similar varieties. Rea,[57] in 1676, described the Yellow Egg under “Magnum Bonum or the Dutch Plum” as “a very great oval-formed yellowish plum, and, according to the name, is good as well as great.” The Imperial, which afterward became the Red Magnum Bonum, is mentioned by Parkinson[58] in 1629 as “Large, long, reddish, waterish and late.” Earlier names in France, how early cannot be said, were Prune d’Oeuf, yellow, white, red and violet, or the Mogul with these several colors, and the Imperiale with the three or four colors. Later the name d’Aubert was applied to the Yellow Egg. Though this fruit was first known in England as the Imperiall, and later as the Magnum Bonum, it has been grown for at least two centuries in that country as the Yellow Egg, and under this name came to America in the latter part of the Eighteenth Century. Koch[59] places these plums in the Date-plum family. The varieties of this group now grown and more or less well-known are Yellow Egg, Red Magnum Bonum, Golden Drop and Monroe.

The characters which readily distinguish the Yellow Egg group are,—the large size of the fruit, possibly surpassing all other plums in size, the[33] long-oval shape, more or less necked, yellow or purple color and the yellow flesh. The plums are produced on tall, upright-spreading trees.

The Imperatrice Plums.—This is a poorly defined assemblage of varieties, of which dark blue color, heavy bloom, medium size and oval shape are the chief characters. It is impossible to trace the origin of the group or to refer varieties to it with accuracy. The Imperatrice, of which Ickworth is an offspring, seems to have been one of the first of the blue plums to receive general recognition, and can as well as any other variety give name to the type. This group contains by far the greatest number of varieties of any of the divisions as here outlined, chiefly because the color, the size, and the shape are all popular with growers and consumers. This has not always been the case, for in the old pomologies, blue plums are comparatively few in number, Parkinson, for instance, giving in his list of sixty in 1629 not more than a half-dozen Domesticas that are blue.

Among the varieties that fall into this group are:—Ickworth, Diamond, Arch Duke, Monarch, Englebert, Shipper, Arctic, Smith Orleans and Quackenboss.

About the only characters that will hold for this large and variable group are those of the fruits as given above, though to these may be added for most of the varieties included in the division, thick skin and firm flesh, clinging stones and poor quality. The trees vary much but are usually hardy, thrifty and productive, making the members of the group prime favorites with commercial fruit-growers.

The Lombard Plums.—Just as the blue plums have been thrown in the last named group, so we may roughly classify a number of red or reddish or mottled varieties in one group. If the oldest name applicable to this group were given it should be called after the Diaper plums, well-known and much cultivated French sorts of two and three centuries ago. Since they are no longer cultivated, and as the Lombard seems to be a direct offspring of them and is fairly typical of the division, the name chosen is as applicable as any. These plums differ but little from those of the preceding group, except in color and in having a more obovate shape, a more marked suture, smaller size and possibly even greater hardiness and productiveness, and if anything, even poorer quality, though to this last statement there are several marked exceptions. In this group are no doubt many varieties which are crosses between some of the old red plums and varieties of the other groups given.

[34]

The following sorts may be named as belonging here:—Lombard, Bradshaw, Victoria, Pond, Duane, Autumn Compote, Belle, Middleburg and Field.

2. PRUNUS INSITITIA Linnaeus

There is a great diversity of opinion among botanists as to what Linnaeus meant to include in his Prunus insititia. His description of the species is not definite and can be made to apply to any one of several very distinct plums. But the botanists who recognize the species usually[35] include in it, among cultivated plums, the Bullaces and the Damsons, plums which differ only in the shape of the fruit, the former being round and the latter oval. Some of the texts noted in the references for this species also place the St. Julien and the Mirabelle plums here. In The Plums of New York the authors consider the Bullaces, Damsons, the St. Julien and the Mirabelles as belonging to this species.

It is true that Linnaeus established at an earlier date than the naming of Prunus insititia his Prunus domestica damascena, in which the varietal name indicates that he meant the Damsons, but the description of the variety taken by him from Bauhin’s Pinax[60] making the plum large, sweet and dark purplish, cannot be made to apply to this fruit, nor can it be connected definitely with any other plum; this being true, and since Linnaeus refers to no type specimen, figure, or locality, his Prunus domestica damascena according to current botanical practices in America, should be rejected.

The trees of the Insititia varieties are readily distinguished from the Domestica sorts in having a dwarfer and more compact habit; much smaller and more ovate leaves with more closely serrate margins; branches more finely divided, more slender, with shorter joints, and bearing spines or spinescent spurs; having a more abundant and a more clustered inflorescence, with smaller flowers, a glabrous instead of a pubescent pistil and calyx-tube; reflexed calyx-lobes where in Domestica they are often erect; and flowers appearing nearly a week later. The number of stamens in Prunus domestica averages about thirty; in Prunus insititia, about twenty-five. The fruit-characters of Prunus insititia are even more distinctive. The fruits are smaller, being less than an inch in diameter, more nearly round or oval, more uniform in shape, never strongly compressed as in Domestica, with a less distinct suture and more often with a pronounced neck. The color is usually the Damson purple or the Mirabelle yellow, with no intermediate colors as in Domestica and with few or but slight variations as compared with the other species. The plums are sweet or sour with a very much smaller range in flavor in the case of the Insititias and withal very distinct from that of Prunus domestica. The stones are smaller, more oval and much more swollen.

In variability the Insititia plums are quite the reverse of the Domesticas, almost wholly lacking this quality. These plums have been cultivated over two thousand years, yet there is seemingly little difference[36] between the sorts described by the Greeks and Romans at the beginning of the Christian Era and those we are now growing. So, too, one often finds half-wild chance seedlings with fruit indistinguishable from varieties under the highest cultivation. This pronounced immutability of the species is one of its chief characteristics.

There are probably several sub-divisions of Prunus insititia but material does not exist in America for the proper determination of the true place for these forms, and the Old World botanists cannot agree in regard to them. It is probable that Prunus subsylvestris Boutigny[61] and Prunus pomarium Boutigny[62] belong to Prunus insititia and almost beyond question Prunus syriaca Koehne[63] is the yellow-fruited Mirabelle of this species. Prunus insititia glaberrima Wirtg,[64] occasionally found in the herbaria of Europe has, with its small, roundish-obovate leaves, but little appearance of Prunus insititia and may be, as Schneider surmises,[65] a cross between Prunus spinosa and the Myrobalan of Prunus cerasifera.

The Insititia plums are second in importance only to the Domesticas. Their recorded history is older. This is the plum of the Greek poets, Archilochus and Hippona, in the Sixth Century B. C.[66] Theophrastus, the philosopher, mentioned it three hundred years before Christ, as did Pollux, the writer and grammarian, a century before the Savior, while Dioscorides, the founder of botany, during the last named period, distinguishes between this plum and one from Syria, presumably a Domestica. This is one of the twelve kinds of plums described by Pliny (see page 17) who calls it the Damascene, so-called from Damascus in Syria, and says of it, “introduced long since into Italy.” It is the Damask plum of Columella when in his tenth book he says:

The yellow plums of the Roman poets, Ovid and Vergil, are probably the Bullaces or Mirabelles of this species. Indeed, its cultivation was probably prehistoric, for Heer[67] has illustrated and described stones of a plum found[37] in the lake-dwellings of Robenhausen which can be no other than those of Insititia.

The authentic written history of this plum may be said to have begun with or a little before the Christian Era. The records of the cultivation and development through the early centuries of the present chronology and the Middle Ages to our own day may be found in the herbals, botanies, pomologies, agricultural and general literature of the past two thousand years.

Prunus insititia now grows wild in nearly all temperate parts of Europe and western Asia—from the Mediterranean northward into Norway, Sweden and Russia. The botanists of Europe very generally agree that its original habitat was in southern and southeastern Europe and the adjoining parts of Asia, and that elsewhere it is an escape from cultivation. Hooker[68] says that Prunus insititia grows in western temperate Himalaya, cultivated and indigenous, from Gurwhal to Kashmir, the type being that of the “common yellow-fruited Bullace.” A few botanical writers hold that it is truly wild in the parts of Europe where now found growing. There are also not a few botanists who, as has been stated in the discussion of the Domestica plums, unite the Insititias with the Domesticas, and others who combine these two with the Spinosa plums in one species, Prunus communis.[69]

It is possible that the species is occasionally found naturalized in eastern United States; several botanists so give it.

Wherever the habitat of the Insititia plums may have been, practically all writers from the Greeks and Romans who first mention this fruit to those of the present time, connect the cultivated varieties in one way or another with the old Semite city, Damascus. It is almost certain that the Syrians or Persians were the first to cultivate these plums, and that they were unknown in Europe as domesticated varieties until the Greeks first and the Romans afterward came in intimate contact with the people of the Orient. Thus it is often stated in the old pomologies that Alexander the Great brought these plums from the Orient after his expedition of conquest and that some centuries later Pompey, returning from his invasion of the eastern countries, brought plums to the Roman Empire.

The history of the Insititia plums in America has been given in the main in the discussion of the Domestica plums, for the varieties of the two[38] species have never been kept separate by plum-growers, all being grouped together as European plums. It is probable, however, that the Damson plums of this species were earlier introduced and more generally grown than any other of the European plums by the English settlers of America, as the references to plum-growing before the Revolution are largely to the Damsons. The reasons for this early preference for these plums are that they come true to seed while most varieties of the Domestica do not; and trees and cions were not readily transportable in colonial times; and, too, the Damsons have always been favorite plums with the English.

When the first American fruit books were published at the beginning of the Nineteenth Century the Damsons and Bullaces were widely grown, for all writers give a relatively large number of varieties of these plums and speak well of them. Thus McMahon,[70] in his list of thirty plums gives six that belong here, ending his list with “Common Damson, etc.,” as if there were still more than those he enumerates. Prince, in his Pomological Manual, in 1832, gives at least eighteen sorts that may be referred to Insititia with the statement that one of them, the Early Damson “appears to have been brought to this country by the early Dutch settlers, or by the French who settled here at the time of the revocation of the Edict of Nantes,” adding, “It is much disseminated throughout this section of the country.” At the end of the Eighteenth Century Deane’s[71] New England Farmer or Georgical Dictionary, in a discussion of plums in general says: “The most common plum in this country is the Damascene plum, an excellent fruit for preserving, which is said to have been brought from Damasam, hence the name.”

The hardiness, thriftiness and productiveness of all of the varieties of this species commend them to those who cannot give the care required to grow the less easily grown Domesticas, and in America, as in Europe, these plums are to be found in almost every orchard and in many communities half-wild, thriving with little or no care. The fact that they are easily propagated, growing readily from suckers and coming true to seed is an added reason for their general distribution.

The Insititia plums do not seem to hybridize freely with other species—at least there are no recorded offspring of such hybrids, though Koch believes the Reine Claudes to be a hybrid group between this species and the Domesticas and there is much evidence in the fruit to show that the[39] French Damson is part Domestica. The tree-characters of the Insititia plums are such, especially as regards vigor, hardiness, productiveness and freedom from disease, as to seemingly make hybrids with them very desirable. That this species can be hybridized with Domestica, at least, is certain from work done at this Station where we have made a number of crosses between them.

Four groups of plums, the Damsons, Bullaces, Mirabelles and St. Juliens, in all eighty-six varieties mentioned in The Plums of New York, may be referred to this species. There are so few real differences between these divisions, however, that it is hardly possible, logically, to sub-divide Insititia plums into more than two groups. But since the groups of plums given above are so often referred to in pomological works it is necessary to discuss them.

The Damsons.—The description given the species fits this division of it closely, the differentiating character for the fruit, if any, being oval fruits, while the Bullaces, most nearly like these, are round. The origin of the Damsons, as we have seen, was in Syria and near the ancient city, Damascus, their written history dating back several centuries before Christ. This plum has escaped from cultivation in nearly all the temperate parts of Europe and more or less in the eastern United States, the wild forms often passing under other names, as the Wild, Wheat, Spilling, Donkey, Ass, Hog and Horse plums. The true Damsons have a fine spicy taste, which makes them especially desirable for cooking and preserving, but a very decided astringency of the skin makes most of the varieties of Damsons undesirable to eat out of the hand; this astringency largely disappears with cooking or after a light frost. Nearly all Damsons are sour, though a few sweet Insititias are placed in this group.

Since the seeds grow readily and the sprouts are very manageable, the Damsons, with the other Insititias, are much used as stocks upon which to work other plums, especially the less hardy and less thrifty Domesticas. Although less used now than formerly for stocks it is a question if these plums, or some of their near kin, do not make the best obtainable stocks. There seems to be much difference in the varieties of Insititia in their capacity to send up sprouts. The forms which send up the fewest sprouts are much the best for use as stocks.

Curiously enough, the Damsons are highly esteemed now only by the Americans and English, being grown much less at present in Continental Europe than a century or two ago. Late pomological works and nurserymen’s[40] catalogs from others than the English or Americans barely mention these plums.

The Bullaces.—It is impossible to distinguish between the tree-characters of the Damsons and the Bullaces, and pomologists are far from agreeing as to what differences in the fruit throw a variety into one group or the other. Some writers call a sour variety of Insititia a Damson, and a sweet one a Bullace; others make color the differentiating character, calling the purple plums Damsons and the light colored ones Bullaces; still others call oval Insititias Damsons and round ones Bullaces. If a distinction is to be made, shape seems to be the character upon which it should be based. The name Bullace applies to the round shape of the fruit, but when first used or by whom given it is impossible to say. It is commonly used in the old herbals and pomologies of both England and Continental Europe, there being many variations of the name, of which bullis and bulloes are most common with the word bullum in frequent use for the fruit of the Bullace tree. The varieties of Bullaces are few in number, and are not largely grown, being known for most part only in fruit collections, the Damsons serving all the purposes for which the Bullaces would be worth growing, and to better advantage.

The Mirabelles.—The Mirabelles are round, yellowish or golden, freestone Insititias, ranging from half an inch to an inch in diameter, very slightly sub-acid or sweet. The trees do not differ from the type of the species unless it be in even greater productiveness than the other groups of Insititia, all of which bear very abundant crops. The fruits represent the highest quality to be found in the varieties of this species, approaching the Reine Claudes of Prunus domestica in richness of flavor. Indeed, the Mirabelles may almost be said to be diminutive Reine Claudes, resembling them not only in quality but in color and in shape, and so closely as to lend color to Koch’s[72] supposition that the Reine Claudes are hybrids between Prunus domestica and Prunus insititia.

In France the Mirabelles are accorded second if not first place among plums, being superseded in popularity, if at all, only by the Reine Claudes. They are used in the fresh state and as prunes, and are freely made into conserves, preserves, jellies and jams, being found in the markets in some of these forms the year round. They are much used for pastry, their size being such that one layer of fruit suffices and is none too deep for a good pie or tart. The fermented juice of these plums is somewhat largely used[41] in the making of a distilled liquor, a sort of plum brandy. The dozen or more varieties of Mirabelles differ chiefly in size of fruit and in time of maturity. The range in size is from half an inch to an inch in diameter and in time of ripening in France from the first of August to the first of October.

The Red Mirabelle frequently referred to in pomological works is Prunus cerasifera, and the name is wrongly so used, for if not first applied to the several varieties of Insititia it now by almost universal usage belongs to these plums. The origin of the word, as now commonly used, dates back over two centuries, being found in the pomological treatises of the Seventeenth Century. The assumption is that Mirabelle is derived from mirable meaning wonderful, and the name was first so used by the French.

Unfortunately the Mirabelles are hardly known in America. These plums have so many good qualities of tree and fruit that American pomology would be greatly enriched if the best Mirabelle varieties were grown in both home and commercial orchards. They should be used in cookery much as are the Damsons, which they surpass for some purposes.

St. Juliens.—The St. Julien that the writer has seen in American and European nurseries is unmistakably an Insititia. At one time St. Julien stocks were used almost exclusively in New York nurseries, and few large plum orchards are free from trees which have through accident to the cion grown from the stock. Such trees bear fruit so like the Damson that one is warranted in saying that the two are identical, and that St. Julien is but a name used for a Damson when the latter is employed as a stock. The fruit is sweetish with a taste identical with that of the sweet Damsons.

Plum-growers who have had experience with plums on several stocks are almost united in the opinion that the St. Julien is the best of all for the Domesticas, at least. St. Julien stocks were formerly imported in great numbers from France, where it is still largely grown for European use. The name seems to have come in use in France more than a century ago, but why given or to what particular Insititia applied does not appear. There is, however, a distinct variety or type of Insititia used by the French in producing stocks, for French pomologists advise careful selection of mother-plants for the production of the young trees by suckers or layers, and caution growers of stocks in no case to use seeds which bring twiggy, spiny and crooked stocks.[73] St. Julien plums are seemingly nowhere grown at present for their fruits.

[42]

There are several ornamental forms of plums which are given specific names by European horticulturists, mentioned in the last paragraph in the discussion of the Domestica plums, which some writers place, in part at least, with the Insititias. These plums are not found in America and it is impossible to place them with certainty in either of the two species upon the contradictory evidence of the Europeans.

3. PRUNUS SPINOSA Linnaeus.

European botanists commonly break the species into a number of sub-species, as:—Prunus spinosa typica Schneider,[74] flower-pedicels and calyx-cup glabrous; Prunus spinosa praecox Wim. and Grab.,[75] pedicels short, blossoms appearing before the leaves; Prunus spinosa sessiliflora Beck,[76] with sessile flowers, possibly the same as the next preceding form; Prunus spinosa coatanea Wim. and Grab.[77], blossoming with the leaves and with long pedicels; and Prunus spinosa dasyphylla Schur.[78], flower-pedicel and calyx-cup more or less hairy. Besides these botanical sub-divisions there are several horticultural forms as follows:

Prunus spinosa flore-pleno of the nurserymen is a double-flowered form, making a beautiful little shrub or small tree much planted in gardens[43] in Europe and somewhat in America. Its blossoms are pure white, about half an inch in diameter and not quite double, as the stamens form an orange cluster in the center of the flower. The flowers are thickly crowded on short spiny branches, the dark color of which forms a striking contrast to the white flower. Prunus spinosa purpurea is another horticultural group, more vigorous than the species, less thorny and with larger foliage. Its branches are erect, purplish in color, striated. The leaves and petioles are at first very pubescent but at maturity glabrous; the upper surface of the leaf is green marked with red, the under a deep reddish-violet. The flowers are a pale rose. One or two variegated forms of this species are also offered by nurserymen.

Schneider holds[79] Prunus fruticans Weihe[80] and Prunus spinosa macrocarpa Wallroth[81] to be crosses between Prunus spinosa and Prunus insititia.

Prunus spinosa, the Blackthorn or European Sloe, is the common wild plum of temperate Europe and the adjoining parts of Asia. It is adventive from Europe to America and is now quite naturalized along roadsides and about fields in many places in eastern United States. Prunus spinosa is considered by some authors the remote ancestor of the Domestica and Insititia plums, but as brought out in the discussion of the last named species, such parentage is very doubtful.

The Spinosa plum is a common and often pestiferous plant in its habitat, the roots forming such a mass that in general it is impossible for any other vegetation to grow in its vicinity. The plant is small, spreading and much branched and bristles with sharp thorns. The leaves are smaller than those of any of the other Old World species, ovate in shape and very finely serrate. The flowers are usually single but sometimes in pairs or threes and are borne in such number as to make a dazzling mass of white; comparatively few of these, however, set fruit. The fruit is round and small, usually less than half an inch in diameter, and, typically, so black as to have given rise to the old saying, “as black as a sloe.” The fruits are firm but rather juicy, with an acid, austere flavor, which makes them unfit for eating out of hand until frost-bitten, when the austereness is somewhat mitigated. The stone is much swollen, with one edge acute.

[44]

European nurserymen now and then offer trees of the Spinosa plum for fruit-growing, sometimes with the statement that the fruit is sweet. But pomologists do not speak highly of these cultivated Spinosas and hold that they are hardly worth cultivation. The wild plums are quite commonly picked for certain markets in Europe, however, especially those in which the Domesticas and Insititias are not common. With plenty of sugar the fruits make a very good conserve. In France the unripe fruit is pickled as a substitute for olives and the juice of the ripe fruit is sometimes used to make or adulterate cheap grades of port wine. In the country districts of Germany and Russia the fruit is crushed and fermented and spirit distilled from it.

The species is quite variable within limits, but since the wild fruits have been used from the time of the lake-dwellers of central Europe, without the appearance of desirable forms, the variations are not likely to give horticultural varieties worth cultivating for table use. The variations in the fruit are usually in color, the size and flavor changing but little. Several ornamental forms are in cultivation, of which the chief ones have been named.

4. PRUNUS CURDICA Fenzl and Fritsch.

The few herbarium specimens that the writer has seen of this species from southeastern Europe strongly resemble Prunus spinosa but Schneider in the above reference describing it from living specimens says that it differs from the species last named as follows: “Lower growth, about one-half as high, spreading squarrose ramification, much less thorniness; leaves more like domestica, when young hairy on both sides, later above nearly and underneath more or less glabrous; petiole shorter, not exceeding one cm.; blooms later, nearly with the leaves, white, about twenty-two mm. in diameter, borne almost always single in this species; pedicel finely pilose, in Prunus spinosa almost glabrous; stamens fewer, about twenty; fruit blue black, stem longer, exceeding twelve mm.”

So far as appears from the few and scant European references to the species it has no horticultural value.

5. PRUNUS COCOMILIA Tenore.

The writer has seen only herbarium specimens of this plant and has taken the description given from European texts. According to Schneider the species has been divided into two varieties by the Italian botanists. Prunus cocomilia typica having oblong-ovate fruit and Prunus cocomilia brutia having round fruit. Schneider holds also that Prunus pseudoarmeniaca Heldr. and Sart.[82] from Epirus and Thessaly is a variety of Prunus cocomilia differing chiefly in having more pointed leaves and smaller oblong-roundish red plums. The same author puts in this species still another plum, a hairy-leaved form from Thessaly which he calls Prunus cocomilia puberula. He places here also Prunus ursina Kotschy[83] which differs only in minor respects from the species, chiefly in having violet-red fruit though Boissier[84] mentions a yellow-fruited plum which he calls Prunus ursina flava. The last named plums come from Lebanon and North Syria.

6. PRUNUS CERASIFERA Ehrhart[85]

Prunus cerasifera, the Cherry plum, first came to notice in pomological literature as the Myrobalan plum, a name used as early as the last half of the Sixteenth Century by Tabernæ-Montanus and given prominence in the Rariorum Plantarum Historum, published by Clusius in 1601. Why applied to this plum is not known. Myrobalan had long before been used, and is still, as the name of several plum-like fruits of the East Indies, not of the genus Prunus, which are used in tanning, dyeing, ink-making and embalming. Until Ehrhart gave it the name Prunus cerasifera in 1789 it was known as the Myrobalan plum by botanists, some of whom, and nearly all horticulturists, have continued the use of the name until the present time.

Not a few of the botanists who have used Myrobalan for this plum have called it a botanical variety of Prunus domestica. Among these were Linnaeus and Seringe. Others, as Loisleur and Poiteau, have preferred the name for the species as distinguished by Ehrhart.

Many of the early botanists, as Tournefort in 1700, Ehrhart in 1701, Loudon in 1806 and Loisleur in 1812, gave the origin of the Cerasifera plums as North America, but upon what authority does not appear. On the other hand many European botanists, including Linnaeus, gave the habitat as Europe or Asia. The supposition that this plum came from North America hardly needs discussion. The plum flora of this continent has been well enough studied so that it can be said that no plant that could by any possibility be the Cerasifera plum grows on this side of the Atlantic. Neither does it seem logical to consider this an off-shoot of Prunus domestica, for fruit and tree-characters are distinctly different, and for a member of the genus Prunus are remarkably constant. Moreover, there is abundant evidence to show that this is a distinct species and that its nativity is in the Turkish and nearby countries in Europe and Asia and that there it has been in cultivation for a long time.

It is very significant that in the old herbals and botanies a frequent name of this fruit is “the Turkish plum.” But more specific and almost conclusive proof is that two forms of plums belonging to this species are known to come from the Caucasus region. Prunus divaricata[86] is now considered[47] by some botanists to be a synonym of Prunus cerasifera and by others to be a botanical variety of the last named species. Ledebour, who named it, found it in the Trans-Caucasian region. It differs from the type only in having much divided, wide-spreading and nearly prostrate branches. The Pissardi plum, a purple-leaved form of this species, originated in Persia. A plum now growing in the Arnold Arboretum raised from seed from Turkestan, presumably from wild stock, is identical with plants of Cerasifera of European origin. And, according to Schneider,[87] this plum is known in the wild state in Caucasus, Trans-Caucasus, northern Persia and Turkestan.

The Cerasifera plums are small trees, usually upright but in some forms with spreading branches which are commonly unarmed, glabrous and brownish in color. The leaves are ovate and smaller and thinner and with more finely serrate margin than those of the Domestica plums. It blooms prolifically and bears large, white, single or paired flowers, making a most beautiful tree when in flower. The fruit is small, round, and cherry-like, from half an inch to an inch in diameter, usually red but sometimes yellow. The flesh is soft, sweetish or sub-acid and poor. The stone is turgid, smooth and pointed. The species is variable in nearly all tree-characters, and were it not surpassed by other plums for its fruit there would undoubtedly be a great number of varieties cultivated for the markets. There are, however, but few cultivated Cerasiferas, only nineteen being described in The Plums of New York. It is very generally distributed wherever plums are grown, because of the use to which it has been put as stocks for other species. For this purpose it is held in high esteem the world over. In the nurseries of New York it is now used more than any other stock and it is common to find it fruiting here and there from plants set for or used as stocks. In fact practically all the cultivated varieties have arisen as survivals of plants meant for stocks. It is almost certain that the Cerasifera, or Myrobalan, as it is universally known by horticulturists, dwarfs the cion and that it is not equally well suited to all varieties; but it does not “sprout” as badly as some other stocks, is adapted to many soils, and the young trees grow well and are rapidly budded, giving at the start a strong and vigorous orchard tree.

The Cerasifera plums are handsome trees. The foliage is a fresh and beautiful green and whether covered with a mass of flowers or loaded with red or yellow fruit these plums are as handsome as any of our cultivated fruit trees, and as desirable for ornamentals.

[48]

The hardiness, thriftiness, freedom from disease and adaptability to soils make the species desirable for hybridizing. A number of breeders of plums have made use of it with some indications of a promising future, several interesting hybrid offspring of this species being described in The Plums of New York.

The small number of varieties of Cerasifera cultivated for their fruit indicates that but little can be expected from this species by plum-growers, since so little has come from it in the shape of edible fruits, though it has been under general cultivation for over three hundred years, at least, as an ornamental and as a stock. Several valuable groups of ornamentals have arisen from Cerasifera, of which the following are most notable:—

In 1880 M. Pissard, gardener to the Shah of Persia, sent to France a purple-leaved plum which proved to be a form of Prunus cerasifera. To this plum Dippel[88] gave the name Prunus cerasifera atropurpurea, while horticulturists very generally call it Prunus pissardi. A close study of the purple-leaved plum reveals no character in which it differs from the species except in the color of foliage, flowers and fruit; the leaves are purple, as are also the calyx and peduncles of the flowers, while the fruit is a dark wine-red. These are but horticultural characters and do not seem to be of sufficient importance to establish for this plant a botanical variety. This view is strengthened by the fact that Jack[89] reports that seeds from the purple-leaved plum have produced plants which agree in all essential particulars with the species; while Kerr[90] has grown a purple-leaved plum from a variety of Prunus cerasifera.

Besides this well-known purple-leaved plum nurserymen offer Prunus pendula, a weeping form; Prunus planteriensis, bearing double white and red flowers; Prunus acutifolia, a plum with narrow, willow-like leaves; Prunus contorta, characterized by twisted, contorted foliage; Prunus elegans, Prunus gigantea, and a variety with yellow and another with variegated leaves, etc. All of these are probably horticultural varieties of Prunus cerasifera though some of them cannot be classified with surety.

Schneider[91] calls Prunus dasycarpa Ehrhart,[92] the Prunus armeniaca dasycarpa of Borkhausen,[93] a cross between Prunus cerasifera and Prunus armeniaca, one of the apricots.

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7. PRUNUS MONTICOLA K. Koch

Prunus monticola is described by the above authors as a shrub-like plum from Asia Minor and Armenia having, so far as can be learned from European texts, little or no horticultural value. The herbarium specimens seen by the writer indicate that this species is closely related to Prunus cerasifera. The description of the species is abbreviated from Schneider.

8. PRUNUS TRIFLORA Roxburgh

A study of the botanical characters of the many Triflora plums under cultivation fails to show any lines of cleavage whereby the species can be divided. Of plums commonly grown in America it is not very closely related to any unless it be Prunus simonii. There are several plums from eastern and central Asia with which we are not at all familiar in America that may show relationship with Prunus triflora, chief of which are Prunus ichangana Schneider,[94] Prunus thibetica Franchet[95] and Prunus bokhariensis Royle,[96] the last a cultivated plum from northern India. These, in herbarium specimens, have some characters reminding one of Prunus triflora, others of Prunus domestica and still others, of Prunus cerasifera.

The Triflora, or Japanese,[97] plums are now cultivated in all parts of the world where plums are grown; yet outside of Japan and China they have been grown for their fruit less than half a century. Despite the fact that these plums have been grown in Asia for several centuries the wild form is not known. Indeed, there are doubts in the minds of some as to whether it constitutes a distinct species, Maximowicz, an authority on the flora of Japan, among others, holding that it is but a form of Prunus domestica. Roxburgh in naming it gave but little definite information in regard to the species, but the herbarium specimens of his in the Kew Herbarium are readily identified as identical with our Japanese plums.[98] The confusion between Prunus triflora and Prunus domestica seems needless, as the points of difference between these two species are several and very distinct and constant, the resemblances between Prunus triflora and[51] some of the American species being much closer. So, too, the effort, sometimes made, to make more than one species out of Prunus triflora is straining a point, for though the types under cultivation vary considerably yet the variations are not greater than between varieties of other species of the genus Prunus.

Prunus triflora is almost certainly a native of China. According to Georgeson and Sargent, who have made extensive botanical explorations in the forests of Japan, there are no indigenous plum trees in that country. Dr. K. Miyake, botanist at the Agricultural College of the Imperial University, Tokyo, Japan, writes to this Station,[99] that Prunus triflora does not grow wild in Japan but was introduced there from China from two to four hundred years ago. Bretschneider[100] in his treatise on The Study and Value of Chinese Botanical Works says that the plum has been cultivated from ancient times in China and this indicates that the original habitat was in that country. Mr. F. N. Meyer, Agricultural Explorer for the United States Department of Agriculture, who has made extensive agricultural explorations in China, writes[101] that he has seen many trees of Prunus triflora cultivated in the Chekiang Province and also about Canton but that he had not found the species growing wild. Roxburgh says[102] that the shrub had been “received from China into our gardens in Bengal.” Forbes and Hemsley[103] state that varieties of this plum are cultivated in China and that it occurs in the wild state in the mountains near Peking as well as on the Tsunglin range in Shensi and Kansu. These writers are, however, uncertain as to where it is truly indigenous.

While the above and practically all evidence points to China as the original home of Prunus triflora it is likely that the habitat of the species cannot be accurately determined until western and southwestern China have been explored by botanists, these regions as yet being almost unknown to foreign scientists.

Notwithstanding the illustrious work of Kaempfer, Thunberg, Siebold and Fortune in sending to Europe the choicest plants of Japan and China, Prunus triflora seems to have reached the Old World through America at a very recent date. At least the species was not cultivated for its fruit in Europe until introduced from the United States as Japanese plums,[52] and even yet they are but barely known in European orchards. The species was introduced into this country from Japan about 1870 by a Mr. Hough of Vacaville, California. According to Bailey,[104] who has given much attention to these plums, Mr. Hough obtained his trees from a Mr. Bridges, United States Consul to Japan. John Kelsey, Berkeley, California, produced the first ripe fruit of the Triflora plums in America in 1876 and 1877, and impressed by their value began recommending them. Owing to Mr. Kelsey’s efforts the propagation of these plums was begun on a large scale about 1883 by W. P. Hammon & Co., of Oakland, who commemorated Mr. Kelsey’s labors by naming the plum after him. The success of the Kelsey started the importation and origination of varieties and a veritable boom in Japanese plums was soon under way.

This fruit is a most valuable addition to our pomology, no less than ninety-two varieties now being under cultivation in America. At first it was thought desirable only for the southern states, but it proved to be nearly as hardy as the Domestica plums in the northern states and was soon widely distributed north and south. Beyond question it has suffered from over-praise, which has led to over-planting. As was of necessity the case, many untested and worthless varieties were offered fruit-growers, and these, with the failure of some of the extravagant claims for the really meritorious varieties, have given the Triflora plums a bad reputation with many fruit-growers. Now we have cultivated plums of this species for forty years and there has been time for the excitement of their discovery and the consequent reaction to abate making it possible to arrive more nearly at their true place in pomology.

The plums of this species possess several striking features that commend them to fruit-growers. Undoubtedly the most valuable attribute of the Triflora plums as cultivated fruits is their wide range of adaptability. All must admit that this group of varieties is less valuable than the Domestica varieties where both succeed, but the Triflora plums are adapted to a much wider range of country and of conditions than the Domesticas. But even where both types of plums succeed the newer plum introduces several very desirable features quite aside from additional variety which the many distinct sorts furnish. Thus, as a species, the Trifloras are more vigorous, productive, earlier in coming in bearing and more free from diseases, especially black-knot and leaf-blight, than the[53] Domestica plums. The Trifloras are also less subject to curculio than most of the native and European species. They keep longer and ship as well as the better known Europeans. As compared with native varieties the plums from Japan are larger, handsomer and better flavored and keep and ship better. Some disadvantages are that they blossom so early as to be often caught by spring frosts; they are quite subject to brown-rot; for most part they are tenacious clingstones; the species, all in all, is less hardy to cold than the Domestica plums; lastly, they are inferior in quality to the varieties from Europe. The last fault is so serious that, though the average for the Triflora plums is high, making them unquestionably more desirable inhabitants of the orchard than any of the native species, they cannot compete with the Domesticas where the two types can be equally well grown.

The botanical differences between these Asiatic plums and those from Europe and America are most interesting. In 1859 Asa Gray called attention to the striking resemblances between the east coast floras of Asia and America. The Triflora plum is one of the plants which furnishes substantial evidence of this similarity and of the dissimilarity of the east and west coast floras of the two hemispheres. In general aspect the trees of the Triflora plums in summer or winter are much more like those of the American species than like those from Europe or West Asia; so, too, the fruits are more alike in appearance and in quality, and the peach-like foliage of the Trifloras might easily be mistaken for that of some of our varieties of Hortulana or Munsoniana. In the manner in which the buds are borne and in vernation the resemblance of the Oriental species to the Americanas, Hortulanas and Munsonianas is again most striking. In Asiatic and American species the buds are borne in twos and threes, while in the European species they are more often single or double.

The importance of this similarity of the Triflora plums to the most common American species is seen when Gray’s reason for the likenesses between the two floras is considered. This, briefly, is that similar types of post-glacial plants should persist in areas having like geographical positions and like climates; hence east-coast plants in one hemisphere should be expected to be similar to those of the east coast of the other hemisphere and the same with the west coast. Triflora plums are near of kin to American plums, then, because they have been evolved under similar conditions. This is a reason why these plums from Japan are adapted to so wide a range of country in America, and why, too, they[54] are so free from the fungus troubles which attack European plums, but from which American plums suffer but little.

As might be expected from their nearness of kin the Triflora plums hybridize readily with the American species and especially with the Hortulanas and Munsonianas, the species they most resemble. Unfortunately an amalgamation of the Oriental plums with the Americanas is not so easily accomplished and that with the Domesticas is still more difficult. Hybrids with Prunus simonii are easily made and the progeny as a rule have much merit. Hybrids of the Trifloras with our native species give most promising results, a number of them being described in The Plums of New York. The fact that the Trifloras have been cultivated for several centuries, at least, means in their hybridization with American species that there is an amalgamation of domesticated characters with the similar but wilder characters of our native species.

It has been very difficult to establish a satisfactory nomenclature for the Triflora plums now grown in America. In spite of the excellent work of Berckmans,[105] Bailey[106] and Waugh,[107] in bringing order out of what was at one time utter confusion, there is still a great deal of uncertainty as to the identification of some varieties. The confusion began with the first extensive importation of these plums from Japan when names which the Japanese applied to classes or groups or the localities from which the plums came were made to apply in America to definite varieties. Many of the names under which the plums were imported have had to be dropped and the varieties boldly renamed. Another source of confusion has been that these, of all plums, seem most variable under changed conditions. Local environment in many instances in America changes somewhat the habit and appearance of varieties, making it difficult to decide whether two or more specimens of the same sort from different localities are identical varieties or distinct. Curiously enough, too, the trees of some varieties of plums seem to bear unlike fruit in different years, especially in the matter of time of ripening; that is, trees of some varieties do not always ripen their fruit in the same sequence, being earlier than another variety one year and possibly later the next. All fruits are more or less variable in this respect, but the Triflora plums are remarkably so, a fact that has added to the confusion in their nomenclature, since it adds to the difficulty of identifying varieties.

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The cultivated varieties of Prunus triflora are also very diverse as regards tree-characters, especially as to vigor, hardiness and time of maturity of the fruit. The differences seem to be horticultural or those that come from cultivation, rather than botanical. Indeed, it seems impossible to place the numerous varieties in horticultural groups that are marked with any great degree of definiteness. A distinction of groups based on color is sometimes made, but the one character is insufficient to have classificatory value. In Japan, according to Georgeson, a division of the species is made with shape as the line of division. He says[108] “The round plums are designated by the term botankio, while those of an oval or pointed shape are called hattankio.” The varieties are sometimes loosely grouped into yellow and red-fleshed sorts. A serviceable classification would have to be founded on several or a considerable number of characters. Such a classification at present is impossible.

9. PRUNUS SIMONII Carrière

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All that is known of the history and habitat of this species is that it came from China in 1867 having been sent to the Paris Museum of Natural History by Eugene Simon, a French consul in China. The spontaneous form has not as yet been found. The general aspect of the tree is more that of the peach than the plum and the drupes are as much like apricots or nectarines as plums but when all characters are considered the fruit can better be classed with the plums than with any of the other stone-fruits named.

Prunus simonii has been widely grown in America both for its fruits and as an ornamental, but it cannot be said that it has become popular for either purpose and only one variety of the species is now under cultivation. As a food product the plums lack palatability and as ornamentals the trees are subject to too many pests. Prunus simonii has been successfully hybridized with Prunus triflora and as secondary crosses its blood has been mingled with that of some of the native species as well. Most of its hybrid offspring have more value than the parent, nearly all of them lacking its disagreeable taste. According to an article published in Revue Horticole[110] a new form of the Prunus simonii was produced in 1890 from a bud sport, the fruit of which is elongated, a little cordate, slightly unequal, and grooved on one side. So far as can be learned this sport has no very decided merits as a horticultural plant.

10. PRUNUS AMERICANA Marshall

As Prunus americana is more carefully studied throughout the great territory it inhabits, undoubtedly one or more sub-species will be described. The plums of this species in the Mississippi Valley are distinguished from the eastern and typical form by fruits having a length greater than the diameter, by a somewhat different aspect of tree and by flatter seeds which are usually conspicuously longer than broad. All of the cultivated varieties come from the western form. The plant of Prunus americana in the dry plain regions in Kansas and Nebraska becomes shrubby in character while on the alluvial bottom lands along the streams in this region it retains the character of a tree. In the southern limit of its range, the leaves of this species are more or less pubescent on the lower surface. As the species occurs throughout western New Mexico, Colorado, Utah, Wyoming, Montana and Manitoba, it differs enough, possibly, from the eastern types to be considered a sub-species, having a wholly different aspect of tree,[58] silvery and somewhat scurfy twigs, smaller, thinner and lighter colored leaves and smaller fruits with more roundish stones.

Prunus americana is the predominating native plum. It is the most widely distributed, is most abundant in individual specimens and has yielded the largest number of horticultural varieties of any of the native species. Because of its prominence and comparatively high degree of permanency of characters it may well be considered the type from which has sprung not only its botanical varieties but several other of the American species. Its variability, too, is shown in its many diverse horticultural varieties, and of its adaptability it may be said that it flourishes on nearly all soils and exposures, and is found wild or cultivated from Maine to Florida and northward from Mexico along the eastern slope of the Rocky Mountains well into Canada. The species was well named by Marshall “Americana.”

This plum has not played nearly as important a part in the pomology of America as its merits would warrant. It seems to have made an impression almost from the first upon the Europeans who settled America, for it is mentioned in nearly all the early records of the food products of the newly found land, yet its cultivation can hardly be said to have begun until the last half of the Nineteenth Century. But the early descriptions of this and other native plums by the colonial explorers, naturalists and botanists, show but little interest in these fruits as subjects for cultivation, and seem to contain almost no prophecies as to the possible development of a new orchard plant from them. It is probable that the Damsons, which were early introduced in America, and the Domesticas, which came at least before the Revolution, proved so adaptable to the part of the New World in which the colonies were planted that this, even though the best of the wild plums, offered small reward in comparison.

It is certain, however, that from the very first, Americana plums were much used by the early settlers as wild fruits, for the histories of all the colonies and states in which plums are found contain innumerable references to wild plums, usually with some expression showing that they were considered makeshifts until the European plums could be grown. Long before white men came to America the possessors of the continent knew and esteemed these fruits of the woods. According to some of the early writers wild plums of this species, since found where the Americanas are dominant, were planted and rudely cultivated by the natives.[111] It[59] is likely, however, that these Indian orchards were more often the result of seeds dropped about camping places and towns rather than regularly planted orchards. It is not improbable that the wide distribution of this species in the Mississippi Valley and the country about and beyond the Great Lakes is due somewhat to the hand of the Indian, of the voyageur and of the missionary of the French regime.

The common names under which this plum passes in the states where it is found as a wild fruit are indicative of the knowledge possessed of it by the people. The Americana is nearly always the wild plum of eastern America. It shares with several other species the names in various parts of the country of Red Plum, Yellow Plum, the Horse and the Hog Plum. In Iowa this is most often the “native plum;” in Indiana it is the Goose plum; in Georgia, the August plum, while in the states bordering on the Gulf it is often called the Sloe.

The domestication of Americana plums is due to the fact that the plums of Europe will not thrive in the Mississippi Valley, the prairie states, nor, for the most part, in the South. The European species are tender both to cold and heat in these regions and they are attacked by those scourges of plum culture, black-knot, leaf-blight and curculio. If, then, the people in the West and South were to have plums at hand when wanted, the wild species had to be brought under cultivation. Where the two will grow side by side it is doubtful if any would choose to grow the Americanas in preference to the Europeans or even for the sake of variety.

The Americana plum was introduced into European gardens at an early date, for references to it are found in the pomological works of the Eighteenth Century, Duhamel having described it in his great work on pomology in 1768, under the name Prunier de Virginie, and later Poiteau[112] gives a very good description of it under the name Prune de la Gallissioniere. Just how much earlier than these dates it was taken to the Old World cannot be said, but seeds of it are likely to have been taken there by some of the returning explorers of early colonial times. The important fact is that as a cultivated fruit it has made absolutely no headway in competition in Europe with the plums of that continent though it is to be found not infrequently as an ornamental.

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The domestication of these plums began less than a century ago, not through direct efforts in breeding them but as the result of the selection of the best of the wild or chance trees found in many widely separated localities. It would be most interesting to follow in detail the introduction of variety after variety of this species into cultivation, giving full credit to the men, many of them pioneers in newly settled countries, through whose efforts the amelioration of the species was begun. But space forbids, and the reader who desires to trace more fully the history and the evolution of these plums must put together the histories of the two or three hundred varieties of Americanas described in the chapters on varieties.

Are the Americanas to compete with the Domesticas, Insititias and Trifloras where all may be grown? It is very doubtful or at least not soon. The Old World plums are so superior, speaking generally, in size, appearance, and flavor, the qualities which appeal to those who eat plums, that the native varieties stand small chance for popular favor. Their place in pomology must long remain the region where the older and more highly developed groups of plums cannot be grown. Though there are now many times more of the Americana plums under cultivation than of the recently introduced Trifloras, the latter are more popular and are likely to remain so in localities where both can be grown.

The range of Prunus americana is seemingly increasing, making it almost impossible to give its present limits. The boundary line of its northern range passes through central New York to central Michigan, southern Wisconsin, Minnesota and South Dakota extending northwestward to Manitoba and reaching its western limit in Utah. It occurs locally southward through Colorado to northern New Mexico. It is rare in Oklahoma and does not occur in Texas, but is represented in Missouri by a pubescent form. East of the Mississippi River the typical species occurs in all of the states from central New York southward to northern Florida. In this great territory it is found in many diverse soils and exposures but responding in all to good soil and congenial environment. In the wild state the Americana plums are most often found along the borders of streams and swamps or in bottom lands where moisture abounds. Sometimes they are found in swamps which may be submerged a part of the year. In spite of a predilection for moist lands, however, the wild plants are not infrequently found on comparatively dry uplands, seeming to prefer soils containing considerable lime. The wild trees are usually found in thickets, often of considerable extent.

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Under cultivation the range is even greater than for the wild plant. It is only in localities of extreme heat and cold, humidity or aridness, that some of the many Americanas cannot be made to grow under conditions at all favorable for orchards of any of the temperate fruits. So, too, varieties may be found for nearly all soils which permit of cultivation. This freedom from local attachments is one of the chief assets of the species.

The Americana tree is commonly small, often but a bush, and usually with a thick, thorny top. Generally the head attains a height of about fifteen or eighteen feet and sometimes it rises to twenty-five or thirty feet, spreading into many rigid branches which are often pendulous at the extremities. The species may almost always be told by the rough, shaggy, grayish bark, the large, thin, persistent plates of which give a very characteristic shagginess. In the spring the tree is covered with umbelliferous masses of pure white flowers and both at this season and later with its ample foliage or showy fruit, the plant is very ornamental. The leaves are large, oval or obovate, thin, dull and veiny, with very jagged margins.

The fruit is reddish or yellowish or a blending of the two with the red varieties predominating. Often the color is more nearly orange than red or yellow—in fact pure yellow fruits cannot be found. Wild or cultivated the fruits of the Americana plums vary greatly in season, size, shape and flavor. In the orchard the period of maturity covers a range of several weeks, beginning in New York in August and ending in October; in the wild, trees in the same thicket may vary as much as three weeks in ripening their fruit. The size of the cultivated sorts is from that of a Damson to that of some of the Gages, the shape being roundish-oval, or quite oval, sometimes oblique and sometimes truncate at one or both ends and often more or less compressed. The wild fruits usually have a pleasant flavor and this is much improved under cultivation so that when fully ripe the flesh of some sorts is sweet and luscious, hardly surpassed, if the skin be rejected, by the best Domesticas. The skin is usually thick, coriaceous, acerb or astringent, and altogether very unpleasant, making with the tenaciously clinging stones the chief defects of these fruits. In some varieties skin and stones are far less objectionable than in others.

The trees of the varieties we have as yet are not very manageable in the orchard. They make a very slow growth and are hard to control, producing at maturity many leaning trunks which are often crooked, as are also the branches which, with the unkempt heads, give an impression of waywardness and wildness. Nearly all of the varieties over-bear and[62] unless thinned the fruits are so small as to be hardly worth harvesting; not infrequently trees die from over-bearing. A few varieties are unfruitful but usually because of defective pollination. Nearly all sucker badly on their own roots, and except in cold regions should be grown on other stocks. In general there are fewer pests to combat with these than with the European plums but yet they are far from being exempt and require on the grounds of this Station quite as much spraying as do other plums.

Waugh, who has given the subject much study, claims that the Americanas are not very strong sexually,[113] chiefly because of defective reproductive organs. He found in extensive examinations that 21.2 per ct. of the pistils were defective, ranging from nothing in some varieties to 100 per ct. in others. More seldom the anthers were defective and the flowers were sometimes proterandrous (the pollen maturing before the pistil is ready to receive it), and that they were rather frequently proterogynous (the pistils receptive before the pollen is mature). Waugh holds that in planting these plums, provision should be made for cross-pollination, and recommends as sorts most suitable for inter-planting for this purpose, other varieties of the same species.

Plant-breeders have not found that this species hybridizes as readily as most of the other cultivated native plums. This is chiefly due to a seeming lack of affinity for other species. Nevertheless there are numerous Americana hybrids, and it is likely that as the high quality of the fruit and the hardiness of the trees become better known they will be used much more for hybridizing.

The Americana plums are all hardy and some of the varieties can be grown as far north as general agriculture is practiced. These, with the Nigras, will probably always be the chief groups for dry, cold regions between the Great Lakes and the Rocky Mountains. They may also be relied upon in the colder parts of New York and New England. The flower-buds as well as the trees are hardy, having been known to withstand a temperature of forty degrees below zero. Goff[114] reports that in the winter of 1896-7 the flower-buds of Domestica varieties on the grounds of the Wisconsin Experiment Station were almost totally destroyed though the minimum temperature recorded was only twenty-three degrees below zero, but the flower-buds of Americana varieties were not at all injured. Since[63] the blossoms open comparatively late there is less damage from spring frosts in this than in most other species even of the natives.

The number of varieties of Americana plums is a testimonial to the merits of the species. There are about 260 varieties of them more or less disseminated. There are many divergent types of these and since all are far from what may be eventually expected from the species the number of varieties will undoubtedly greatly increase and in still other directions. In the meantime the great majority have fallen by the wayside. The weeding-out process seems to be in this case the chief agent of progression. A fault with the varieties now before the public is that many of them are so similar that a difference can hardly be detected. The elimination of the great majority of the varieties of this species now in the catalogs and a much more judicious selection of varieties for future dissemination would relieve pomology of the burden it now carries in the numerous sorts of Americanas.

PRUNUS AMERICANA MOLLIS[115] Torrey and Gray

Prunus americana mollis is a western and southwestern form of Prunus americana, the sub-species being distinguished from the species by the amount and character of the pubescence on the leaves and shoots. The leaves, petioles and shoots of this plum are soft-pubescent, almost tomentose, the tomentum being pale in color and usually very dense; the calyx-lobes are pubescent on both sides and the pedicels are appressed and densely pubescent. According to Bailey, there is a form of this sub-species “with flowers as completely double as those of St. Peter’s wreath, or similar spireas.” This double-flowering plum we have not seen.

It is impossible to give the range of Prunus americana mollis as the woolly-leaved plum of the west gradually passes into the smooth-leaved species of the east and the two forms are not infrequently mixed in the South and Southwest; or possibly it would be better to say that they run into each other though the extreme forms are sufficiently distinct as to be readily mistaken for separate species. It can only be said[64] that it is to be found in the greatest abundance in the region extending from southern Iowa through Missouri. Only two varieties of this plum, Wolf and Van Buren, are in general cultivation, both of which originated in Iowa. In neither fruit nor tree-characters do these differ greatly from the Americana plums.

A plum with pubescent leaves belonging to the Americana series known locally as the Big Tree plum, occurs from western Tennessee, south-westward through the extreme southern portion of Missouri, through Arkansas, southern Oklahoma, extending westward in central Texas, at least, as far as the Colorado River and reaching its southwestern limit in northern Mexico. From specimens of this plum in several herbaria and from studies made of it in the field by W. F. Wight of the United States Department of Agriculture, it would seem that this plum is a distinct species, its chief distinguishing character being the great size attained by the tree. So far as it is known the Big Tree has no cultivated forms unless it be Bilona, supposed to be a hybrid between this species and Prunus triflora, now growing on the grounds of F. T. Ramsey, Austin, Texas.

11. PRUNUS HORTULANA Bailey[116]

Prunus hortulana as established by Bailey, to quote a part of the original description, “includes a large class of plums represented by Golden Beauty, Cumberland, Garfield, Sucker State, Honey Drop, probably Wild Goose and others.” Unfortunately Bailey later added[117] a number of other plums to the group which the above varieties and some ten or fifteen others comprise, the additions in themselves constituting at least three somewhat distinct groups, and then to account for this omnibus species called it a “brood of natural hybrids.” Waugh supports Bailey’s conclusions[118] and divides the species into four groups of hybrids—the Miner group, the Wild Goose group and the Schley or Clifford group. These, Waugh says, “form an unbroken series from Prunus americana to Prunus angustifolia.” The fourth of Waugh’s groups, “comparatively distinct[66] from the others, is made up of such varieties as Wayland, Moreman, Golden Beauty, Reed, Leptune, Kanawha and others.” These plums he designated as the “Wayland group.” This disposition of the plums under consideration leaves Prunus hortulana as the name of only a rather loosely related lot of cultivated varieties. It is probable that neither Bailey nor Waugh, had they seen the material now to be had, would have left the species as they did.

There is an abundance of herbarium material to show that Prunus hortulana as originally described by Bailey, with the varieties named as the type, leaving out Wild Goose, which is but doubtfully included, and as represented by Waugh’s “Wayland group,” is to be found wild in Illinois, western Kentucky, western Tennessee, Missouri and northern Arkansas, Oklahoma and southeastern Kansas. The writer has not seen material from states adjoining those named but the species is probably more widely spread than the range given indicates. Further, the cultivated varieties named by Bailey as members of his species, to which should be added at least American Golden, Benson, Columbia, Crimson Beauty, Dunlap, Kanawha, Leptune, Moreman, Reed, Wayland and World Beater, are so similar in all their characters and constitute a group so distinct from any other species that it is impossible to place them otherwise than in a distinct species. A group of hybrids could hardly be so uniform, and, moreover, these varieties contain characters, like late blooming, late fruiting, color, texture and flavor of fruit, leaf-serrations and deposits of red cork-cells in the bark, which other native species do not have, thereby shutting out the probability of the hybridity theory in which the supposed parents are Prunus americana and Prunus angustifolia. Lastly, and most convincing, varieties of the species come true to seed, which of course, would not be the case were these plums hybrids. From seed borne in 1893 this Station has had six seedlings of World Beater and four of Golden Beauty attain the age of sixteen years with more or less fruit for thirteen successive years. The seedlings could hardly be distinguished from the parents and showed no pronounced characters of either of the species of which Prunus hortulana has been supposed to be the hybrid offspring.

Of the sixteen varieties named as certainly belonging to this species, ten came from wild plants or seeds. Two of the remainder came from planted seeds and the origin of the remaining four is not known. One of the varieties from the wild, Golden Beauty, if its history as commonly given is correct, came from the Colorado River in western Texas. The[67] Golden Beauty now under cultivation almost certainly belongs to Prunus hortulana, though it differs somewhat from other varieties of the group, but how it could have come from the wild in western Texas, so far from the usual range of the species, is at present unexplainable. This and other idiosyncrasies of distribution were reasons given by Bailey and Waugh for calling this species a group of hybrids. A careful study of localities from which all other Hortulana varieties than Golden Beauty have come shows them to be well within the range of Prunus hortulana. The fact that Golden Beauty is perfectly hardy at Geneva, and according to Waugh fairly so at Burlington, Vermont, suggests either that what we have as Golden Beauty did not originate in south central Texas or that the plant from which it came must have been introduced there within comparatively recent times.

Prunus hortulana gives to American pomology a very distinct and valuable group of plums which fortunately are adapted to a wide range of conditions, especially of climate. The Hortulanas are particularly well suited to the Mississippi Valley and southern states and fruit well as far north and east as New York. The product of Wayland, Kanawha and Golden Beauty, best known of the plums under discussion, is especially suitable for preserves, spicing and jelly, being unsurpassed by any other of our plums excepting the Damsons for these purposes. They are quite too acid and the flesh clings too tenaciously to the stone for dessert plums or even for ordinary culinary purposes. These plums, having firm flesh and tough skins, ship and keep splendidly and since they are the latest of the native plums in ripening, extend the season for this fruit very materially. The Wayland-like plums make very good stocks upon which may be grafted not only the varieties of the same species but those of the other native species as well. A point of especial merit with these plums as stocks is that they do not sucker as do most other species. Unfortunately they cannot be propagated from cuttings and the difficulty of obtaining seed at present precludes their use very generally. The Hortulana plums hybridize freely with other native species and their hybrids are such as to commend this species very highly to plum-breeders for hybridization.

Waugh[119] has given the name Prunus hortulana robusta to a group of hybrid plums of which Prunus triflora and various native varieties are the parents. For most part these hybrids resemble the American more[68] than the Asiatic parent. Since these plums differ so among themselves it is doubtful if more can be said as to the characters of Waugh’s group than to mention the above resemblance. Some thirty or more varieties fall into this group of which America, Golden, Juicy, Ruby, Waugh and Gonzales are chief.

PRUNUS HORTULANA MINERI Bailey

It is impossible from present knowledge to say certainly whether the Miner-like plums put by Bailey into a botanical sub-division of Prunus hortulana are extreme variations of the species or, as Bailey in his last accounts and Waugh at all times have supposed, are hybrids between Prunus hortulana and Prunus americana. It is certain that all of these plums are intermediate in some characters between the two species named; neither botanists nor pomologists can agree as to whether certain varieties belong to the one or the other botanical division. There are, however, in several herbaria, specimens from the wild, and from different localities, that indicate that there is a distinct plum toward the northern limit of the range of Prunus hortulana which, if a natural hybrid, is of so ancient hybridity that the plants now come measurably true to type. The chief representatives of the Miner-like plums under cultivation, as Miner, Forest Rose, Prairie Flower and Clinton, are so like these wild plums as to lead the writer to believe that Bailey’s botanical sub-division is justified and is worth continuing even though a considerable number of the varieties now put with Miner, most of which have originated under cultivation, are hybrids and that the wild plums may have come from natural hybrids of more or less remote time.

The sub-species differs from the species in having shorter, stiffer, less graceful branches; leaves smaller, thicker, rougher and of a bluish-green cast; the blossoms of the two are much the same but those of the sub-species open a few days earlier; the fruits of the sub-species are larger than those of the species, lighter red, have more bloom, are less firm in texture, ripen earlier, yet later than those of any other species, and are quite different in flavor, having more nearly the taste of the fruit of Prunus americana; the stones, as well as the fruits, are very different, being in the sub-species larger, broader, flatter, smoother and less pointed. The differences in fruit and stone, and to some extent in the leaves, can be seen if the color-plates of Forest Rose and Wayland be compared.

[69]

In fruit-growing, the Miner-like plums behave in general much like the Americana plums. In some respects the fruits are an improvement upon those of the Americana varieties. For example the skin in the Miner-like varieties is usually less tough; is brighter in color and the flavor, in most cases, is a little better. These plums seem to be nearly or quite as hardy as the Americanas and are adapted to quite as wide a range of soils. Presumably they have the same value as stocks, though they seem not to have been tried for this purpose and they should have equal value at least in plant-breeding. The trees of the Miner-like plums are rather more amenable to domestication than those of Prunus americana having as orchard plants straighter trunks, more symmetrical and less unkempt tops and making larger trees. The fruits ripen so late as to make the varieties of this group especially valuable in prolonging the season for plums in regions where native varieties are grown exclusively. About twenty varieties of this sub-species are under cultivation.

12. PRUNUS NIGRA Aiton

It is possible that a group of Nigras, those occurring in western Wisconsin and Minnesota and about the upper extremity of Lake Superior ought to be described as a sub-species since they have a somewhat different aspect of tree and the fruits are a darker shade of red and show more bloom; the calyx is more pubescent and the calyx-glands more sessile. The differences in environment may change these characters, as indicated above, but they seem very constant in the cultivated varieties of the groups, most of which come from the west, and therefore sufficient to segregate this form from the species.

The Nigra is the wild plum of Canada. Its most common name, “Canada Plum,” is distinctly applicable and is here supplanted by “Nigra” only for the sake of uniformity. This is undoubtedly the dried plum which Jacques Cartier saw in the canoes of Indians, in his first voyage of discovery up the St. Lawrence in 1534.[120] These primitive prunes, Cartier says, the Indians called “honesta.” In his second voyage, the next year, he enumerates among other fruits the plum, “prunier,” growing on the “Ysle de Bacchus,” named from its “Vignes.” Dried plums, we learn from many later accounts, were a staple article of the winter diet of the savages. That the Indian tended the trees is probable, for the early explorers often record that plantations of plums were found about the aboriginal towns. Undoubtedly the range of this species was greatly extended by the Indians.

The Nigra is the most northern of the American plums, being an inhabitant of a region bounded on the north by a line passing from southern[71] New Foundland westward to the Strait of Mackinac and thence southward to Lansing, Michigan. Its southern boundary can be but illy defined, but the species is common in New England, northern New York, where it is sometimes cultivated about houses, and westward at least as far as the eastern shore of Lake Michigan for the species, while the western form reaches the western boundary of Minnesota at least. Small[121] reports it as far south in the Appalachian System as northern Georgia. In the great region outlined above it is distributed in more or less scattered localities, being found usually in the valleys of rivers and streams, though often on high lands and in open woods, in the last locations preferring a limestone formation.

There has been much discussion as to whether Prunus nigra should be given specific rank or be united with Prunus americana, either as a part of that species or as a botanical variety of it. Until the revival by Sargent in 1892 of the name given the group by Aiton in 1789, the botanists of the latter half of the Nineteenth Century had for most part described the two groups under Prunus americana. Since Sargent’s re-establishment of the species, botanists have very generally regarded it as worthy of the rank. Bailey and Waugh, the leading horticultural authorities on plums, however, consider Nigra as but a botanical variety of Americana. The taxonomic characters of Prunus nigra seem to the writers of The Plums of New York to be as distinct as those of several other of the native species of Prunus, and since the species now is generally recognized by botanists, we have considered it in this work as distinct from Prunus americana.

The two species may usually be distinguished by the following differences: (1) The general aspect of the trees is very different. The tree of Americana is larger, the top is more spreading, and its branches longer, with more twigs, more slender and more pendulous. The bark on the trunk is lighter-colored and much more shaggy than in Nigra. (2) The wood of Nigra is tougher and the trees do not break as readily as those of Americana. The wood is also lighter in color. (3) The leaves of Nigra are larger, broader and the serrations are not so deeply incised nor so often double. Very distinct and very constant are the glands to be found on the teeth of the serrations on the young leaves of Nigra. These glands disappear as the leaves grow older, leaving a calloused point which makes the serrations of Nigra rounded, while those of Americana are acute, this[72] being one of the most constant differences. (4) The flowers of Nigra appear several days earlier, are larger and are more pink than those of Americana. (5) The calyx-lobes of Nigra are glandular and the leaf-stalks are biglandular, characters usually not found in Americana. The calyx in all its parts is glabrous or at least far less pubescent than in Americana and if present the hairs are short and stiff, whereas in Americana the pubescence is soft. (6) The fruit of Nigra ripens earlier and is darker in color with less bloom and is more oblong than that of Americana. The skin of the plum is thinner and is not so objectionable either cooked or eaten out of hand. (7) The stone of Nigra is usually larger, flatter and more strongly crested. The characters of the two species vary much in different individuals and there are many intermediate forms but the differences seem as constant as between other species of this variable genus.

The Nigra plums are important horticulturally because they can be grown in somewhat colder regions than the Americanas. They not only endure more cold than the last named group, but their tough wood enables them to stand better the weight of snows and the stress of winds. Their earliness, too, prolongs the season for this type of fruit and in regions where the season is short they may be grown with more certainty than other groups. In habits and characters other than those named they are so like the Americana as to need no further discussion. About forty varieties of this species are under cultivation.

13. PRUNUS ALLEGHANIENSIS Porter

In leaf, flower and tree Prunus alleghaniensis resembles Prunus americana. The species has long been known to be distinct, however, having been first distinguished by J. R. Lowrie of Warriorsmark, Pennsylvania, in 1859,[122] and was published as such in 1877, when T. C. Porter of Lafayette College described it as Prunus alleghaniensis. It differs from Prunus americana chiefly in the smaller size of the plant, smaller leaves and flowers, in color of flowers which fade to pink in this species, and in fruit-characters. The fruit matures earlier, is much smaller in size, is more globose, and is a dark purple or blue with very heavy bloom. The skin is thick and tough and while the texture of the flesh is as good as that of the wild Americanas the flavor is much more astringent. The stone is more swollen. The plant is commonly but a shrub, usually found along fence rows and the borders of woodlands, but intermingled among old thickets of this kind there are often a few small trees. It is a hardy species, very productive, and seemingly but little attacked by either insects or fungi, being especially exempt from black-knot.[123] In the wild state it produces great numbers of suckers which seem to spring very readily from a bruise or an exposed root.

The range of Prunus alleghaniensis is exceedingly limited. It is found in abundance only in a small territory in central Pennsylvania, being of most frequent occurrence in the barrens of northern Huntingdon County, extending from there north into Center County and northwestward over the Alleghany Mountains into Clearfield and Elk counties. It grows for the most part in elevated lands of the wildest character, being found on low, moist soils, on high and dry barrens and on limestone cliffs, reaching its greatest size in the last situation.

Specimens identified as Prunus alleghaniensis have been found in at least two places in Connecticut and the writer has just seen specimens of a closely allied form collected by W. F. Wight of the United States Department[74] of Agriculture a few miles south of Houghton Lake, Roscommon County, Michigan.

This plum is not yet introduced into cultivation and it is doubtful if the wild fruits have sufficient merit to make an attempt at domestication promising. While the wild fruits are locally used for various culinary purposes it is so much inferior to other native plums, being almost uneatable unless cooked, that its cultivation would hardly warrant the effort. Arboretum specimens of the tree show it to be somewhat desirable as an ornamental, being a small, compact, upright plant, very floriferous, and bearing an abundance of rather attractive fruit.

14. PRUNUS SUBCORDATA Bentham

Prunus subcordata, the Pacific or Western plum, is an inhabitant of the region east of the Coast Range from southern Oregon to central California. It is so rarely found on the seacoast as to have escaped the attention of the early botanists and remained unknown until the middle of the Nineteenth Century, when Hartweg, working in the interior of[75] California, brought the plant to notice. This wild plum is not common except in the foothills of the Sierra Nevadas in northern California and southern Oregon, where it often forms thickets of small trees along streams, thriving in fresh, fertile, sandy soils, in canons, on hillsides or in the forests of yellow pine which are found in this region. Hammond[124] writes of it growing here as usually a small tree but often seen as a shrub from four to five feet high. Of the frequency of the occurrence he says: “It often sets the whole countryside ablaze in the autumn, with the abundance of its scarlet and crimson colors, mingled, of course, with red and yellow, and garnished with a sprinkling of green.” Sandberg[125] reports having collected Prunus subcordata as far north and east as Nez Perces County, northern Idaho, in the Craig Mountains at an altitude of about 2,900 feet, but this report is based on an error in determination, the specimen collected by Sandberg being clearly a European species. The tree and the fruit vary greatly according to the locality.

This Subcordata plum is one of the standard food products of the aborigines in the region in which it grows, being eaten either raw or cooked; and it is sometimes dried in considerable quantities at the harvesting places and carried considerable distances to the Indian villages.[126] The trappers, the first men to enter the habitat of this plum, followed by the gold-seekers and ranchers, all knew and esteemed the fruit. The early settlers regarded it as the most useful of all the wild fruits of the Coast and attempts were made at an early date to domesticate it. Of these Wickson says:[127]

In its typical form Prunus subcordata is a shrub and is often only a low bush but under the most favorable conditions it attains the dimension and shape of a small tree. In its roundish, roughish leaves it so closely resembles the Old World types of plums that it becomes the nearest approach to them to be found among our American species. But in the globular, red or purple subacid fruit it betrays its affinity to the American plums, as it does also in the flat, sometimes turgid, smooth stone to which the flesh tenaciously clings. The flowers are white, fading to rose and borne abundantly, making the plant an attractive ornamental in blooming time as it is also in the autumn when the foliage turns to brilliant red, scarlet or crimson with touches of yellow. The fruit is sometimes so poor in quality as to be inedible but on the other hand is sometimes quite equal to some of the cultivated plums, especially in its botanical variety, Kelloggii.

That the fruit is capable of improvement by the selection of seedling varieties and useful in hybridizing with other species can hardly be doubted. Luther Burbank, under date of December 6, 1909, writes in this regard as follows:

Wickson[128] reports that the roots of Subcordata have been used more or less as stocks for other plums but show no marked advantages over the species commonly used for this purpose. Most of those who have experimented with it condemn it as a stock because it dwarfs the cion and suckers badly.

Prunus oregana Greene[129] is from its description an interesting plum of which, however, it has been impossible to secure a glimpse even of herbarium material and of which we can therefore, only publish Greene’s description as follows:

“Evidently allied to P. subcordata, but leaves little more than an inch long, subcoriaceous, pubescent on both faces, in outline oval or broadly elliptic, never subcordate, commonly acutish at both ends, serrulate; flowers unknown; fruits in pairs or threes, on pedicels one-half inch long or more, densely tomentose when very young, more thinly so, yet distinctly tomentulose when half-grown.

“Known only from specimens collected on the Yanex Indian reservation in southeastern Oregon, by Mrs. Austin, in 1893; and a most remarkable species, as connecting true Prunus with Amygdalus. But that it is a plum and not an almond is evident.”

Without any first-hand knowledge of this species it is thought best to consider it only under the allied species, Prunus subcordata.

PRUNUS SUBCORDATA KELLOGGII Lemmon

Prunus subcordata kelloggii, named in honor of Dr. Albert Kellogg, an early explorer and settler in California, is distinguished from the species[78] in being a somewhat taller and more slender plant.[130] The branches and bark are of a characteristic ash-gray, so distinct in color from Prunus subcordata that this is often called the “Gray-branch” plum. The leaves are orbicular or elliptical, not cordate, cuneate at the base and nearly glabrous. The fruit is bright yellow instead of red and larger than that of the species, being an inch or more in diameter with a more nearly free stone. This plum inhabits the region of Mount Shasta where it has been known since the time of the early gold diggers, attracting more attention as a food, and promising more for the cultivator than Subcordata. Botanists seem to have given this plum comparatively little attention and careful study may give it specific rank. Locally, and now somewhat in the trade, it is known as the Sisson plum, after a Mr. Sisson, living near Mount Shasta, who has brought it to notice. At present the Kelloggii seems to be the branch of promise for the improvement of the wild plums of the western coast.

15. PRUNUS UMBELLATA Elliott

[79]

Prunus umbellata, the Sloe, Black Sloe or Hog Plum, Oldfield, and sometimes Chickasaw and Bullace of the South, is found along the seaboard from South Carolina to central Florida, thence westward to the Gulf and along its shores to Texas. Inland it is found as far north as middle Georgia,[131] Alabama and Mississippi and southern Arkansas. Though very common in localities in the region outlined, there are vast areas of this territory in which it is scarcely found, preferring bottom lands of rivers and rich, moist soils in some instances and dry, sandy copses, open woods and borders of fields in others. In flower and fruit it is a handsome and conspicuous plant, yet, as the references show, the early botanists did not describe it, and even Elliott, who gave it its name, in 1821, passed it by with a scant description. Its neglect by the several famous botanists of the Eighteenth Century who explored this region must be attributed to their confusing it with Prunus angustifolia and Prunus maritima, one or the other of which is found in most of the region, and to the idiosyncrasies of the distribution of Prunus umbellata.

The fruit of this species is unfit for dessert purposes but is commonly gathered for culinary use and sometimes is offered for sale in the markets of the South, being highly esteemed for pies, jams and jellies. There appear to have been no efforts made to domesticate it, however, and since it is quite inferior in fruit-characters to others of the native plums, efforts to that end are probably not worth while.

PRUNUS UMBELLATA INJUCUNDA (Small) Sargent

In 1898 Small described Prunus injucunda as a new species from what had hitherto been considered a part of Prunus umbellata. Sargent, whom we follow, gives it as a botanical variety of Prunus umbellata. Small says that the two differ as follows: Prunus injucunda has “a more rigid habit and the foliage, including the branchlets, is velvety tomentose. In place of the sub-globose drupe of Prunus umbellata we find an oblong fruit of an extremely bitter taste. The stone is correspondingly lengthened.” To these differences may be added tomentose or pubescent leaves, hairy umbels, and tomentose calyx and pistil, as characters not found in Prunus umbellata though there are occasional pubescent individuals in the species.

Small first collected Prunus injucunda in sandy soil in the granite districts about the base of Little Stone Mountain, Georgia, and reports it as occurring about Stone Mountain. Mohr reports the plant on rocky summits and among the sandstone cliffs of Alpine Mountain, Talladego County, Alabama, as a low, unsightly shrub, four feet in height, with short, straggling branches. The wild fruit is seldom fit for domestic use and with so much better material in other species the fruit-grower can hardly afford to spend time in an attempt to domesticate this one.

16. PRUNUS MITIS Beadle

[81]

Prunus mitis is a newly named species from Alabama, common in dry soils in the regions where it is found wild. The species has many characters in common with Prunus umbellata to which it is so closely related that it is difficult to distinguish the two in herbarium specimens. Although nothing is yet known of its horticultural possibilities the apparent relationship does not indicate much value in the plum for the cultivator.

17. PRUNUS TARDA Sargent

Prunus tarda, locally known as the Sloe, as are many other plums, was named from specimens collected in 1901 near Marshall, Texas, by Sargent and others. Sargent, to whom is due what field knowledge we have of the plant, gives its range from where found in Texas to western Louisiana and southern Arkansas. He says that it resembles and is often confounded with Prunus umbellata but may be distinguished from it by its bark, which differs from that of any other American plum tree, being more like that of the chinquapin chestnut with which it grows; by the pubescence on the leaves, not usually found on those of Prunus umbellata; and by its variously colored fruit which ripens much later than that of other plums in the region. From what has been published in regard to the species one gathers little in regard to its horticultural possibilities though the[82] statements that it bears great quantities of fruit and is used locally for culinary purposes indicate that it may have some value under cultivation.

18. PRUNUS ANGUSTIFOLIA Marshall

The original home of Prunus angustifolia is not known. The inference is left in most of the botanies that the species is not indigenous in the region east of the Mississippi, but that it was brought by the aborigines from the southwestern section of the Mississippi Valley or possibly the southern Rocky Mountains or Mexico. The chief reason for the belief[83] that it does not belong where it now grows is the fact that it is usually found near human habitations and on the margins of fields and as it was known to have been cultivated by the Indians,[133] it is supposed to have escaped from their semi-cultivated plantations. Bailey[134] dissents from the current view, holding that the plant behaves like a true native in regions where he has known it, Maryland in particular. It seems to the writer that Bartram’s supposition, given in the foot-note below, has been followed too closely. A careful study of recent botanical works indicates that the species is indigenous to the southeastern United States.

Whatever the original habitat may have been it is now found in the wild state from southern Delaware to Florida and westward to the Panhandle of Texas and southern Oklahoma. It is usually found on rich soils but is found as well in worn-out fields and pastures, most often in thickets of small trees or thorny shrubs or scraggly bushes, producing under the latter conditions a small fruit so like cherries as to give it the name in some localities “Mountain Cherry” (Maryland), and in others “Wild Cherry” (Louisiana).

There has been much confusion in regard to Prunus angustifolia. The older botanists very generally mistook this species for Michaux’s Prunus chicasa which, as stated in the foot-note on page 82, is almost certainly not the plum under discussion. Practically all horticulturists ascribe to Prunus angustifolia a great number of cultivated varieties which cannot by any possibility belong here; indeed, it is doubtful if the species is cultivated at all other than very locally, and still more doubtful as to whether, as compared with other native plums, it is worth growing. In spite of this confusion the species is one of the most distinct of plums, and its characters are comparatively constant throughout the range. A careful reading of Humphrey Marshall’s description of Prunus angustifolia by subsequent botanists might have helped to keep this plum in its place. Marshall wrote of it:

“Prunus angustifolia. Chicasaw Plumb. This is scarcely of so large a growth as the former [P. americana], but rising with a stiff, shrubby stalk, dividing into many branches, which are garnished with smooth, lance-shaped leaves, much smaller and narrower than the first kind [P.[84] americana], a little waved on their edges, marked with very fine, slight, coloured serratures, and of an equal shining green colour, on both sides. The blossoms generally come out very thick and are succeeded by oval, or often somewhat egg-shaped fruit, with a very thin skin, and soft, sweet pulp. There are varieties of this with yellow and crimson coloured fruit. These being natives of the Southern states, are somewhat impatient of much cold.”

The tree-characters given by Marshall are hardly those of the plum under cultivation which we have been calling Prunus angustifolia, and his statement that the species is “impatient of much cold” at once separates the cultivated “Angustifolias” from the true species. We shall contrast the tree-characters of the two groups of plums in the discussion of Prunus munsoniana. Of the hardiness of the two it may be said that the cultivated varieties which we have placed in the last named species are for the most part hardy as far north as Burlington, Vermont, while the true Prunus angustifolia cannot be grown to fruiting as far north as Geneva, New York. Its behavior, too, on the northern limit of its range, and the fact that it did not follow the aborigines northward as it seems to have followed them from place to place within its range, show that Prunus angustifolia belongs in the southern states.

This plum was well known by the early colonists of Virginia and southward. John Smith in Virginia, in 1607-9, and Strachey, writing a few years later, saw “cherries much like a damoizm, but for their taste and cullour we called them cherries.” Beverly in his History of Virginia, written in 1822, speaks of two sorts of plums, “the black and the Murrey Plum, both of which are small and have much the same relish with the Damasine”; the latter was probably the Angustifolia. Lawson in his History of Carolina speaks of several plums,[135] one of which, the Indian plum, must have been the fruit of the present discussion. Bruce[136] quotes[85] a letter from William Fitzhugh, written in 1686, in which the latter speaks of the “Indian Cherry,” meaning of course, this plum; for it still passes under the same name.

Of the horticultural possibilities of Prunus angustifolia, little can be said from this Station as the trees cannot be grown here. But since the species has been so long known, and is so near at hand to fruit-growers, without more of its offspring coming under cultivation, it is not likely that it may be counted upon to bring forth much in the future for the orchard. Such trees and fruits of this species as the writer has seen are not at all promising for the cultivator.

PRUNUS ANGUSTIFOLIA WATSONI (Sargent) Waugh[137]

Prunus angustifolia watsoni is the Sand plum of the plains, being an inhabitant of southern and southeastern Nebraska and central and western Kansas and possibly passing into western Oklahoma. It is usually found along the banks of streams and rivers where it often forms shrubby thickets. The wild plums are held in high esteem for dessert and culinary purposes, becoming a commercial product in parts of the region in which they grow, and are occasionally transplanted to the garden or orchard. From such transplantings a half dozen varieties have arisen. The productiveness, hardiness to heat and cold and the size and quality of the fruits should attract plum-growers in the region of its habitat and experimenters elsewhere as well. Waugh[138] gives the following interesting sketch of the use to which this plum has been put in Kansas:

The sub-species is easily mistaken for the species; in herbarium specimens it is almost impossible to distinguish between them, but in general the Sand plum differs from Angustifolia in its dwarfer habit, shorter-jointed, zigzag, ashy-gray branches, smaller but thicker leaves, larger, thicker skinned and better flavored fruit which ripens later, and in a smaller and somewhat differently marked stone. In distinguishing the two groups some allowance must be made for the adaptability of plums to different environments.

PRUNUS ANGUSTIFOLIA VARIANS Wight and Hedrick

Yellow Transparent may be considered a typical variety. Type specimens in the Economic Collection of the Department of Agriculture were collected at the Eastern Shore Nurseries of J. W. Kerr, Denton, Maryland, (flowers) I. Tidestrom, April, 1910; (foliage and fruit) P. L. Ricker No. 2933, June 29, 1909.

In the wild, Prunus angustifolia varians forms dense thickets, the larger specimens attaining a height of ten or twelve feet. When budded and grown in the orchard it assumes the form of a small tree with well defined trunk and spreading branches, sometimes armed with rather slender spinescent branchlets. It is distinguished from the species by its usually more robust habit, by its having the young twigs less reddish and approaching a chestnut-brown in color, rather longer leaves, longer pediceled flowers, and by the stone in most cases being more pointed at the apex. Usually in more fertile soil than the species, it occurs locally from southern Oklahoma through eastern Texas southward possibly to the Colorado River, and probably westward to the Panhandle region. As yet, however, its distribution is not well defined.

Nearly all of the early ripening horticultural varieties previously referred to Prunus angustifolia belong to Prunus angustifolia varians. The fruit of the sub-species appears to be superior to that of the species though scarcely equal to that of the other southern plums now cultivated. Hybrids between this form and Prunus munsoniana undoubtedly occur freely both in the wild state and under cultivation. The varieties Eagle and El Paso have probably originated in this way. Nearly all of the plums belonging to this species, some twenty in all, are tender to cold, none, so far as is known, succeeding in the North. African, Cluck, Jennie Lucas and Yellow Transparent may be named as representative varieties.

19. PRUNUS MUNSONIANA[139] Wight and Hedrick

The description of this species is based on both wild and cultivated material, and the variety Arkansas may be considered as a typical[90] representative. Type specimens, deposited in the Economic Collection of the United States Department of Agriculture, were collected by W. F. Wight (flowers) at the New York State Experiment Station, Geneva, New York, No. 2721, May 15, 1909, and (foliage) at the Iowa Experiment Station, Ames, Iowa, No. 4178, September 15, 1909.

This species differs from Prunus angustifolia, with which it has long been confused, chiefly in being a much larger plant, a true tree while the other seldom reaches the size of a tree. It has coarser and less twiggy branches, shaggier bark and less red in the color of the young wood. The leaves are larger, thicker, more truly lanceolate in shape, less folded, a lighter green and less glossy. The flowers of the new species are larger, fewer in number, borne in less dense umbels which are not so nearly sessile as those of the older species and are borne on longer pedicels. The calyx-lobes are erect in this species and reflexed in Prunus angustifolia, strongly marked by marginal glands in Prunus munsoniana and eglandular in Prunus angustifolia. The fruits are larger and wholly plum-like in the newly made species and cherry-like in Prunus angustifolia. The stone is very plum-like in Prunus munsoniana but in the older species it might easily be mistaken for the pit of a cherry. The robust form is hardy as far north as Geneva, New York, at least, while the other species cannot be grown much north of Mason and Dixon’s line.

Of the varieties which certainly belong to this species by far the greatest number have originated under cultivation. There is herbarium material from uncultivated plants to show that this species is rather common in the northern part of Texas, in eastern Oklahoma and in parts of Missouri. It is a species forming dense thickets in its native habitat, where it is usually found in rather rich soils, with the older central specimens sometimes attaining a height of twenty to twenty-five feet and gradually diminishing in height to the edge of the thicket. When budded and grown in the orchard it forms a well-defined trunk and attains a height of twenty-five feet or more. The branches are little or not at all spinescent, bark of the stem in young specimens reddish or chestnut-brown, and usually rather smooth, becoming scaly and losing its reddish color with age, that of the young twigs usually chestnut-brown. Its natural range, though not yet definitely determined, probably extends from central Tennessee through northern Mississippi, northern Arkansas, central Missouri and southeastern Kansas to the valley of the Little Wichita River in northern Texas.

[91]

The Wild Goose varieties, now placed here, in the past have been considered hybrids more closely resembling Prunus hortulana than any other species. But Wild Goose and some other varieties of its group are not to be distinguished from Prunus munsoniana and beyond question belong in this species. The varieties in this division of Munsoniana are largely seedlings of Wild Goose, each variety possibly with a different male parent since Wild Goose seldom or never fruits unless cross-fertilized. Thus, of these plums, twelve are known seedlings of Wild Goose; seven others originated under cultivation; the origin of fourteen is not known and it is not certain that any beside Wild Goose came from wild plants. From such a record, and from the characters of the plants, it is probable that some of the Wild Goose varieties are horticultural hybrids, many of them from H. A. Terry of Iowa in whose work, with many varieties of several species, hybridity was the rule.

Horticulturally, this is the most important group of native plums for the South; it contains a greater number of cultivated varieties than any other native species excepting Prunus americana, no less than sixty sorts being listed in The Plums of New York, some of which are deservedly the best known of the native plums for either home or market use. For dessert or the kitchen they are particularly valuable, having a sprightly vinous flavor making them very pleasant flavored to eat out of hand or when cooked. Their bright colors, semi-transparent skins and well-turned forms make them very attractive in appearance. Considering the juiciness of most of the varieties, these plums ship and keep well. Unfortunately nearly all of the varieties of this species are clingstones. This group hybridizes more freely than any other of the plums and there are a great number of promising hybrids of which it is one of the parents. Of all plums, these are most in need of cross-pollination, some of the varieties being nearly or, as in the case of Wild Goose, wholly self-sterile. While these plums are especially valuable in the Southern States, some of them are desirable in the North as well, where all will grow at least as far north as central New York. Plums of this species are occasionally but not often used as stocks. Some recommend them for stocks for low or wet lands. The fact that Prunus munsoniana suckers very badly will probably preclude its use largely in propagating.

The leading varieties under cultivation of this species are Arkansas, Pottawattamie, Robinson, Newman, Wild Goose and Downing, all of which are described in full and illustrated in colors in The Plums of New York.[92] The first four of these have in the past been referred by botanists and pomologists to Prunus angustifolia and the last two to Prunus hortulana.

20. PRUNUS MARITIMA Marshall

Prunus maritima, or as it has long been known, the Beach plum, is as yet hardly grown as a domesticated fruit. It is destined, however, in the minds of not a few, because of qualities which we shall describe, to play a more important part in the future of the cultivated plum flora than it has in the past. It has several valuable characters that should fit it alike for direct cultivation and for hybridizing with other species. It is surprising that more has not been done to domesticate the Maritima plums[93] for they were among the first fruits noticed by early explorers and have always been used by both Indians and Whites for culinary purposes. The fact that Domestica plums thrive in their habitat is the only explanation of the non-amelioration of this plum before this.

September third, 1609, Hudson entered the river bearing his name and found “a very good harbor, abundance of blue plums, some currants brought by the natives dried and the country full of great and tall oaks.” The blue plum was the Maritima; and from Hudson’s time nearly all of the accounts of the New World given by early explorers mention this plum. It is probably one of the plums described by Captain John Smith as a cherry “much like a Damson;” by Edward Winslow in 1621, in a letter to England to a friend, as one of his “plums of three sorts”; by Francis Higginson in his New England’s Plantation in 1630; described by Thomas Morton in 1632 in his New English Canaan as having “fruit as bigg as our ordinary bullis.” John Lawson, one of the first of American naturalists, describes them rather more fully as follows:[140] “The American Damsons are both black and white, and about the Bigness of an European Damson. They grow any where if planted from the Stone or Slip; bear a white blossom, and are a good fruit. They are found on the Sand-Banks all along the Coast of America. I have planted several in my Orchard, that came from the Stone, which thrive well amongst the rest of my Trees. But they never grow to the Bigness of the other Trees now spoken of. These are plentiful Bearers.” These are but a few of the many references to the Beach plum but they are enough to show that the colonists were attracted by this wild plum found on a long stretch of the Atlantic seaboard—probably the first fruit to attract attention from Virginia to New England.

To be more explicit as to its range, Prunus maritima, in its typical form, is an inhabitant of the sea beaches and sand dunes from New Brunswick to the Carolinas, or possibly farther south, growing inland usually as far as recent ocean soil formations extend. As it leaves the seaboard marked variations make their appearance, chief of which are, smaller, more oval, smoother and thinner leaves and smaller fruit. The species has been reported as an inhabitant of the sands at the head of Lake Michigan,[141] but the writer, who is well acquainted with this region, has never seen it there, nor is it to be found in the chief herbaria of Michigan as having been collected in the state.

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In the region where it is found wild the Maritima plum is a rather common article of trade. The fruit is usually sold by the quart, the price being five or ten cents, and is used for both dessert and culinary purposes though for most part for the latter.

The species is one of the most variable of the true plums and there is, probably must ever be, much disagreement as to its botanical relationships. Several botanical varieties of Prunus maritima have already been named and there are yet groups within the species which seem to be nearly as distinct as those described and possibly worth distinguishing. Since the variations show in the size, color and edible qualities of the fruit, as well as in the characters of the plant, it is to be expected that the species has a horticultural future though at present it has but one cultivated variety—Bassett. Professor J. W. Macfarlane of the University of Pennsylvania has shown well the great range of variations in this plum both from botanical and horticultural aspects.[142] He holds that these variations are sufficiently distinct to make many varieties of this plum in the wild, to which DeVries agrees with the statement that they indicate “the existence of separate races as elementary species.”[143] The plum which Small has described as Prunus gravesii, to be discussed later, is a marked variation of Prunus maritima.

As it grows on the sea-coast Prunus maritima is a low bush three to six feet high, occasionally reaching a height of ten or twelve feet. Usually the plant is straggling but sometimes it is compact or even tree-like. Inland, on better soils, or under cultivation it makes a rather handsome dwarf tree. The flowers are borne in great numbers, completely covering the plant and coming later than most of the plums bloom. The species bears fruit very abundantly, which is always attractive but of quite diverse value for food. The fruit varies in size from a half to three-quarters of an inch in diameter and is almost spherical, though sometimes oval and with or without a distinct suture. The usual color is a rich bluish-black with a waxy bloom, but red, yellow, amber and orange fruits are often found. In taste the Maritima plums range from inedible to nearly as rich a flavor as is found in the best of the Domestica plums. Besides variations in the above and other qualities, Macfarlane calls attention to the range in ripening of the fruit of this plum, showing that it extends over a period of two months, an exceptionally wide variation for a wild plant.

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This plum has a number of qualities that commend it to the fruit-grower. Since in the wild it grows on sandy soils it is not likely under cultivation to make great demands on either the moisture or the fertility of soils. It is very hardy and very productive and seldom fails to bear. It seems to be free or nearly so from some of the pests of cultivated plums. Lastly, the great number of wild varieties of the plums give many starting points from which to breed cultivated varieties. Two objections to the wild fruits are that when the fruit is harvested the juice often exudes from the wound made by the parting from the stem, and secondly, the secretion of some substance forming a dark colored, hard core in the pulp which gives a very bitter taste to the fruit. The last defect is very common in the wild plums and is probably due to the sting of an insect. Under cultivation it may be possible to obtain fruits free from these faults.

It would be desirable if some of the characters enumerated above could be combined with those of other species. Burbank has hybridized the Maritima plum with other species, with promising results. Of these he writes under date of December 6, 1909, as follows:

21. PRUNUS GRAVESII Small

Prunus gravesii is now known only in Connecticut, where it is found on a gravelly ridge at Groton near Long Island Sound. It grows in the neighborhood of Prunus maritima to which it is evidently closely related. Small in describing the species gives the following differences between the Gravesii and the Maritima plums: (1) Prunus gravesii is more slender and delicate in habit, and matures its leaves and fruit earlier in the season. (2) The leaf of Prunus gravesii is small and sub-orbicular while that of the other is larger and more elongated. (3) The new species has smaller flowers with sub-orbicular petals while those of Prunus maritima are broadly obovate and gradually narrowed at the base. (4) The fruit of Prunus gravesii is smaller and more globose and has shorter pedicels. (5) The stone is more turgid and is pointed only at the base; that of Prunus maritima is usually pointed at both ends. (6) Sprouts arising from the[97] ground do not produce flowers as they frequently do in the case of Prunus maritima.

The cultivation of this plum has not been attempted and as compared with Maritima it promises little for the fruit-grower.

22. PRUNUS ORTHOSEPALA Koehne

The history and habitat of Orthosepala are given by Sargent as follows: “The history of this plant as I know it, is briefly this: In June, 1880, Dr. George Engelmann of St. Louis, sent to the Arnold Arboretum a package of seeds marked ‘Prunus, sp. southern Texas.’ Plants were raised from these seeds and in 1888, or earlier, they flowered and produced fruit, which showed that they belonged to a distinct and probably undescribed species. A name, however, was not proposed for it, and in 1888, probably, plants or seeds were sent to Herr Spath, of the Rixdorf Nurseries, near Berlin, where this plum was found in flower by Dr. Emil Koehne, who has described it under the name of Prunus orthosepala.”

Of the affinity of this species Sargent says: “Prunus orthosepala is a true plum, rather closely related to Prunus hortulana, from which it can be distinguished by the smaller number of glands of the petioles, by the eglandular calyx-lobes, the dark colored fruit and smoother stone.” As the writer has seen this plum growing in the Arnold Arboretum, Jamaica[98] Plains, Massachusetts, and the City parks at Rochester, New York, it seems well worth cultivating. Mr. J. W. Kerr writes of it as follows:

W. F. Wight of the United States Department of Agriculture has collected specimens of a cultivated plum, taken from the wild, locally known as the Laire, in Rooks and neighboring counties in Kansas, with foliage very similar to Prunus orthosepela. While the identity of Laire with the species under discussion cannot be established at this time, the reported source of the seeds, “southern Texas,” from which Prunus orthosepela was grown may be an error.

23. PRUNUS GRACILIS Engelmann and Gray

Prunus gracilis is found in dry, sandy soils from southern Kansas and western Arkansas to central Texas. It grows most abundantly and thrives best in Oklahoma, a fact which leads Waugh to call it the “Oklahoma” plum. All who know the species agree that it is a near approach to Maritima in many of its characters. This plum is very variable and some of its forms seem not to have been well studied. As a fruit plant Gracilis is hardly known in cultivation though Torrey says it is cultivated in the region of its habitat under the name Prairie Cherry. The wild fruit is used more or less locally and is sometimes offered for sale in the markets of western towns. The quality is about the same as that of the[99] wild Americanas and under cultivation would probably improve. The small size of plant and fruit are the most unpromising characters though the species is also much subject to black-knot.

24. PRUNUS RIVULARIS Scheele

The preceding description is largely compiled from the authors given in the references, the writer having seen only herbarium specimens. The species is included here largely upon the authority of Professor C. S. Sargent of the Arnold Arboretum and W. F. Wight, who know the plant as described by Scheele in the field. Gray described the plant as “verging to Americana.” Bailey says “it evidently bears the same relation to Prunus americana that Prunus watsoni does to the Chickasaw plum.” Waugh is “convinced that Prunus rivularis Scheele is nothing more than one of the more distinct sub-divisions of the multiform hortulana group.”[144] T. V. Munson writes me that the Waylandi plums belong in this species. My own opinion is, from the herbarium specimens examined, from correspondence and conversation with those who have seen the plant in the field, that Scheele’s species is a good one and quite distinct from the species named by Bailey, Waugh and Munson as allied to it. It is to be looked for along the streams and bottom-lands in the neighborhood of San Antonio and New Braunfels, Texas. The plum is locally known as the Creek plum and in common with other plums is gathered for home consumption. The species seems to offer but few possibilities for the fruit-grower.

Ten states produced over 82 per ct. of the plum crop of the United States in 1899. The census of 1900 shows that in the preceding year the total crop in the country was 8,764,032 bushels of which California, Oregon, New York, Washington, Michigan, Iowa, Texas, Arkansas, Ohio and Kansas, named in order of yield, produced 7,429,248 bushels. All other states yielded 1,334,784 bushels. Of these ten states, three, California, Oregon and Washington, holding first, second and fourth places in production, use by far the greater parts of their crops for prunes. Four others, Iowa, Texas, Arkansas and Kansas, grow the native and Triflora varieties almost exclusively. New York with a crop of 313,668 bushels in 1899, Michigan with 213,682 bushels the same year and Ohio with 81,435 bushels, grew the main crop of Domesticas for the states in which plums are not made into prunes.

At the end of the Nineteenth Century the plum ranked third in commercial value among orchard products, being surpassed by the apple and the peach. The increase in number of trees and bushels of fruit for the whole country for the decade ending with 1899 was remarkable, being for trees 334.9 per ct. and for bushels of fruit 243.1 per ct. These great increases were due to very large planting of plums for prunes on the Pacific Coast and to the widespread distribution during these ten years of native and Triflora varieties. It is very doubtful if the percentage of increase has been nearly so great during the present decade. It is likely that the development of rapid transportation and refrigerator service between the great plum-growing region of the far West and the markets of the East has caused a decrease in trees and production in the eastern states.

Plum-growing, as with the growing of all fruits, is confined to localities geologically, climatically and commercially adapted to the industry. If we take New York as an example we find that plums are grown largely only in ten of the sixty-one counties, according to the census of 1900. These with the number of trees in each are as follows: Niagara 184,133, Ontario 92,917, Seneca 59,205, Monroe 57,246, Schuyler 48,336, Orleans 41,985, Yates 32,742, Albany 32,373, Erie 30,281, Wayne 30,047. Over 62 per ct. of all the trees in the State are in these counties and probably they produce more than 90 per ct. of the plums sent to market.

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A canvass of the acreage of four hundred plum-growers in New York shows that the following in order named are the leading commercial varieties: Bradshaw, including Niagara, which is identical, Reine Claude including its several near variations, Italian Prune, German Prune, Lombard, Shropshire, Grand Duke, Washington and Gueii. Abundance and Burbank are as widely distributed as any of these, chiefly owing to the zeal with which nurserymen have sold these varieties, but are seldom grown exclusively in commercial plantations, and their popularity is now on the wane as is also the case with Red June which has been largely planted. Varieties of native plums are hardly grown in New York though now and then they are found in home collections and there are a few small commercial plantations of them.

The fruit of the native and Triflora plums is so inferior to that of the Domestica sorts for market and domestic purposes, that varieties of these are not likely to take the place of the Domestica plums. Producers and purchasers are now familiar with the possibilities of the natives and of the Orientals and have not been greatly attracted by them in New York. It is true, however, that the natives have been chiefly represented by Wild Goose and the Trifloras by Abundance and Burbank—scarcely the best that these groups of plums can produce. It is true, too, that the varieties have been greatly over-praised and that they now suffer from the reaction. Yet the Domesticas command the market and their reliableness in the orchard gives them a popularity in this region which other plums cannot for a long while trench upon.

This brings us to a discussion of the conditions under which plums are now grown in North America and more particularly in New York. Of these, climate, with this fruit, should be first discussed, outranking all others in importance.

CLIMATE

Climatic conditions determine the culture of the plum not only for a region but for a locality; not only as to whether it is possible to grow plums at all but as to whether this fruit can be grown with reasonable prospects of commercial success in competition with other localities. The constituents of climate which are important in plum-growing are temperature, rainfall and air currents, the last two being largely dependent upon the first. The relationship existing between plums and these factors of climate are fairly well known for they have received attention from the very beginning of plum culture.

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There are four phases of temperature that need to be considered in order to get a clear insight into the climatic conditions which govern production of fruit crops. These are, the daily, monthly and annual changes in temperature and the extremes in temperature. Of these the daily and annual changes are of little importance. All plants are very adaptable to daily variations in climate and are little affected by them. Annual variations are shown by statements of the annual mean temperatures but such statements are of small value to fruit-growers as they may be the result of averaging very divergent temperatures or temperatures very close together. The monthly mean, however, is a very fair criterion of climate for fruit-growing, especially when given with the amount and distribution of rainfall.

But far more important than any of the above phases are the extremes in temperature and more particularly of cold. A plant can not be grown profitably where the temperature, even occasionally, falls below the point where winter-killing results to tree or bud, or where the blossom is injured by frost. Extremes of heat are disastrous usually only when long continued. For each fruit, too, there must be a total amount of heat available to carry it from the setting of the fruit to maturity, in which respect varieties of any fruit may differ materially. Of the injurious effects and of the necessary amounts of heat, however, we know but little.

These general considerations of temperature lead us to their application to the plum and especially to a discussion of the most important of the several factors—hardiness.

Hardiness to cold, a matter of prime importance with all fruits, is especially so with the plum because of the many different species, each with its own capacity for withstanding cold. As the different species are taken from their natural habitat to other regions, there to become acclimatized, and as new forms originate by hybridization, the matter becomes more complicated and more important. Waugh[145] has investigated the hardiness of plums and we publish a table given by him showing the hardiness of representative varieties of the species most generally cultivated. We have taken the liberty of adding a few plums not given in the original table and have also made some changes in the nomenclature of the groups.

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Table Showing the Hardiness of Representative Varieties of Plums at Various Places.

h—hardy; hh—half-hardy; t—tender.

A few general statements in addition to the above table will help to make plain the comparative hardiness of the different groups of cultivated plums. The Nigras may be rated as the hardiest of the plums to be considered though the Americanas are but slightly less hardy. The plums of these species are the hardiest of our tree-fruits and are able to resist nearly as much cold as any other cultivated plant. The Insititias, as represented by the Damsons, at least, come next hardiest after the above species, with varieties of Domestica, as Arctic, Lombard and Voronesh,[104] nearly as hardy. So far as resistance to cold is concerned the Domestica plums as a class are less hardy than the apple, ranking in this respect with the pear. Of the Domesticas the Reine Claude plums are as tender to cold as any though some consider Bradshaw as more tender. Between these last sorts and the hardiest varieties there is a great range in capacity to endure cold, as would be expected with so large a number of varieties originating in widely separated climates. The Triflora plums vary more in hardiness than any other of the cultivated species. Speaking very generally they are less hardy than the Domesticas, the hardiest sorts, Burbank and Abundance, being somewhat hardier than the peach, while the tenderest varieties, of which Kelsey is probably most tender, are distinctly less hardy than the peach. Of the remaining plums, the Hortulana, Munsoniana and Watsoni groups, there are great diversities in opinion as to hardiness. Probably all of the varieties in these last groups are as hardy as the peach with a few sorts in each more hardy than the peach. It is to be expected from the more northern range of the wild prototypes that the Hortulana and Watsoni plums are somewhat hardier than Prunus munsoniana.

The rainfall is of comparatively small concern to plum-growers in America, since, with now and then an exception, in eastern America it is sufficient under proper cultivation, and on the Pacific Coast the crop is largely grown under irrigation. Summarized statements of annual rainfall are of little or no importance since almost all depends upon the distribution of the amount throughout the year and upon the manner in which it falls. Monthly and seasonal “means” of precipitation, as in the case of temperature, may be of considerable importance in determining the desirability of a locality for plums.

Air currents are of local or regional occurrence and though not often the determinant of profitable culture of plums have sometimes been important factors in choosing a location to grow this fruit. The occurrence, direction, moisture condition and temperature are the attributes of air currents usually considered. The failure of many plums to grow in the prairie region of the Mississippi Valley and the Great Plains is no doubt due in some measure to winter winds. The problem of varietal adaptation is more or less complicated in any region by the nature of the air currents.

An extremity of any of the constituents of what we call “weather” endangers the plum crop at blossoming time. In New York stresses of[105] weather are probably the predominating causes of the non-setting of fruit on plum trees which bear an abundance of blossoms. This is well shown in a study of the relations of weather to the setting of fruit made by the New York Agricultural Experiment Station in which it is held that several phases of weather at blossoming time cause the loss of plum crops.[146] Thus late frosts, wet weather, low temperature, strong winds and wide daily ranges in temperature were factors in the loss of fruit crops in all of the failures during a period of twenty-five years. Quite as significant was the fact that in all of the years during this period when there was sunshine and warm, dry weather during blossoming time there were good crops of fruit.

Locations for growing the different varieties of plums are selected with reference to general and local climate. As regards general climate, latitude, altitude and proximity to large bodies of water are the chief determining characters; as regards local climate, the lay of the land has most to do as a determinant. Again, varieties are selected with reference to time of blooming, that they may escape in some degree injurious climatal agencies. Lastly, varieties are selected having greater capacity, from one cause or another, to withstand injurious weather. With all varieties it is found that cultural treatment to induce strong vitality helps a tree to withstand stresses of harmful weather at blossoming time.

The above considerations show that the blossoming dates of plums should be known for the proper culture of this fruit. In the following table averages of the blooming dates of varieties of plums for the eight years just past, 1902 to 1909, inclusive, are given.

In making use of these dates, consideration must be given to the environment of the orchards at Geneva. The latitude of the Smith Astronomical Observatory, a quarter of a mile from the Station orchards is 42° 52′ 46.2″; the altitude of the orchards is from five hundred to five hundred and twenty-five feet above the sea level; the soil is a stiff and rather cold clay; the orchards lie about a mile west of Seneca Lake, a body of water forty miles in length and from one to three and one-half miles in width and more than six hundred feet deep. The lake has frozen over but a few times since the region was settled, over a hundred years ago, and has a very beneficial influence on the adjacent country in lessening the cold of winter and the heat of summer, and in preventing early blooming.

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The dates are those of full bloom. They were taken from trees grown under normal conditions as to pruning, distance apart, and as to all other factors which might influence the blooming period.

An inspection of the table shows that there is a variation of several days between the time of full bloom of the different varieties of the same species. These differences can be taken advantage of in selecting sorts to avoid injury from frost. The same table shows the ripening season of the plums growing on the Station grounds. Now and then the late and very late plums given in the table may be caught by fall frosts in the colder parts of New York or in regions having a similar climate.

Table Showing Blooming Dates and Season of Ripening.

The “blooming date” is that of full bloom.

Under season of ripening “very early” is from July 15 to August 10; “early,” August 10 to August 20; “mid-season,” August 20 to September 10; “late,” September 10 to September 20; “very late,” September 20 to October 1.

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THE POLLINATION OF PLUMS.

One of the discouragements in plum-growing is the uncertainty which attends the setting of the fruit in some varieties even though the trees bear an abundance of blossoms. Blooming, the prelude of fruiting, had little significance to the fruit-grower until the discovery was made that many varieties of several fruits were unable to fertilize themselves and that failures of fruit crops were often due to the planting of infertile varieties. Investigations as to the self-sterility of pears, plums and grapes have shown blossoming-time to be one of the most important life periods of these fruits. The knowledge obtained by workers in this field has to some degree modified the planting of all orchard-fruits and of none more than of the plums. Indeed, it is held by many that it is hardly safe to plant any excepting the Domestica and Insititia plums without provision for cross-pollination.

A variety is in need of cross-pollination when the pollen from its own blossoms does not fecundate the ovules of the variety. There is a delicate and complicated procession during the process of fruit formation and the life of the fruit may be jeopardized by any one of a number of external or internal influences. These deleterious influences are most often unfavorable weather or defects in the reproductive organs of the plants themselves. Of the latter, in the plum there are several rather common ones which cause self-sterility, as impotency of pollen, insufficiency of pollen, defective pistils and difference in the time between the maturity of the pollen and the receptiveness of the stigmas.

It is held that the main cause of the infertility in plums is impotency of pollen on the pistils of the same variety. The pollen may be produced in abundance, be perfect as regards appearance, and potent on the pistils of other varieties but wholly fail to fecundate the ovaries of the variety from which it came. The most marked examples of such impotency are to be found in the native plums though the Triflora sorts are generally accredited with being largely self-sterile and the Domesticas somewhat so. The proof offered to show the impotency of plums is for most part the records of fruit setting under covered blossoms. In this method of testing the impotency of pollen there are several sources of error and the figures given by experimenters probably greatly exaggerate the infertility of plums, but since the experience of plum-growers generally affirms the results in some measure it is well to hold that the native plums at least should be so planted as to secure cross-pollination. It is doubtful if the[111] Domestica and Triflora plums are self-sterile and yet the question is an open one as regards some varieties of these species.

There is great difference in the quantity of pollen produced by the several groups of plums but it is very doubtful if insufficiency of pollen is a factor of any considerable importance in the self-sterility of this fruit. Yet the matter is worth attention because of its bearing upon the selection of pollinizers. Of the several botanic groups, speaking somewhat generally, the Americanas and Nigras bear most pollen; the Munsoniana plums are abundant pollen bearers; the Trifloras seldom show a shortage but bear rather less than the others named; the Domesticas produce pollen abundantly; while the hybrid groups are the most capricious of all the plums in this respect, some varieties bearing much and others but little pollen. Probably the amount of pollen which the flowers of any tree produce is somewhat modified by the climate in which the tree is growing, by the weather and by the vigor of the tree.

Waugh[147] and Goff[148] have shown that self-sterile plums often have abnormal pistils or pistils too weak for the development of fruits. Not infrequently flowers of the plum are without pistils, as occasionally, but less rarely, occurs with the stamens and petals. These abnormalities cannot be very general causes of self-sterility in plums, however, as varieties, or even trees, cannot often be found which are not fruitful if other varieties are growing near them. It is very doubtful if even so much as fifty per ct. of abnormal flowers, seriously jeopardizes a plum crop, as the trees bear, if they blossom at all, several times as many flowers as they can mature plums. But a high percentage of abnormal flowers nearly always indicates a general weakness in fruit-setting.

Another cause often assigned for the failure of plums to set fruit is the difference in time of maturity of stamens and pistils. It is claimed that when these organs do not mature simultaneously the plums do not set unless pollen is supplied from some other source. The task of taking notes at blossoming time on more than three hundred varieties of plums on the grounds of this Station has given abundant opportunity to observe the comparative degrees of maturity of pistils and stamens in varieties of this fruit. In general the pistils mature first, often three or four days before the stamens. Rarely the pollen is disgorged before the stigmas are receptive. But stigmas remain receptive, weather conditions being favorable,[112] for several days and the pollen from all anthers is not shed at once and is produced with such seeming prodigality as to almost insure the retaining of a sufficient amount to pollinate late-maturing stigmas. In view of these considerations, premature or retarded ripening of either pistils or stamens does not seem of great significance in the setting of fruit.

From the statements just made it may be seen that the main cause of the failures to set fruit when trees bloom freely must be ascribed to the failure of pollen to fertilize the pistils of the flowers of the same variety. The solution of the problem of self-sterility in the main, then, is to so plant that varieties will be mutually cross-fertilized. In the selection of varieties for such cross-pollination two factors must be considered, simultaneity of blossoming and sexual affinity.

It is evident, if cross-fertilization is to play an important part in fruit-growing, in planting to secure it kinds must be chosen which come into blossom at the same time as those they are expected to fertilize. The table on pages 106 to 109 shows the sorts that bloom together or nearly enough so to make cross-pollination possible. It will be found upon examining the table that, under normal conditions and during the average season, varieties of any one species overlap sufficiently for the above purpose unless it be the very early and very late varieties. Variations due to locality and to season must be expected but within the bounds of New York these will be slight. If the table is used for other regions than New York it must be borne in mind that the farther south, the longer the blossoming season; the farther north, the shorter the season. Properly interpreted the table of dates should be a useful guide as to the simultaneity of blooming.

Varieties of plums seem to have sexual affinities. That is, some varieties will fertilize each other very well and some will not, even though they belong to the same species. There seems to be little definite knowledge as to the sexual affinities of plums and it is not, therefore, possible to lay down exact rules for the selection of pollinizers for individual varieties. In the current discussions of cross-pollination it is probable that the importance of “affinities” is over-rated, and yet the subject is worthy of consideration. Waugh and Kerr have given this subject considerable attention for native and Japanese plums and have recommended a list of pollinizers for the several species.[149] The Domesticas and Insititias, the[113] above writers hold, are best cross-pollinated by varieties from the same species if cross-pollination is essential.

The subject cannot be closed without the expression of the opinion that the lack of cross-pollination as a cause of the uncertainties in the setting of fruit has been over estimated in the planting of plum orchards. This expression of doubt is made because there are serious disadvantages in the planting of mixed orchards of any fruit and the question as to whether these do not outweigh the advantages must ever be considered.

LOCATIONS AND SOILS FOR PLUMS.

The plum is comparatively easy to suit in the matter of location of orchards, as is shown by the exceedingly wide range of this fruit in New York. Plums are grown with eminent success on the elevated and sloping lands adjoining the Great Lakes, the Central Lakes of western New York and on both banks of the Hudson. Unquestionably there are many other localities than those named about the waterways of the State and also upon the elevated lands in the western interior formed by morainic hills, and upon the slopes of the mountains in eastern New York. Upon any land in the State suited to general farm crops, where the severity of winter is tempered by the lay of the land or proximity to water, and where late spring frosts are infrequent, plums may be grown. The early blooming plums, the Trifloras in particular, require more or less consideration as to the slope of land, a northern exposure to retard blooming-time being best. With other species the direction of the slope makes little difference, though a slope for air and water drainage is always better than a dead level.

The plum is now thriving in New York, and in the country at large, in a great diversity of soils. The chief requisite for the genus in general seems to be good drainage. Given this condition, some sort of plums can be grown on almost any soil found in America not wholly prohibitive of plant growth. Plums can be found which will stand rather more water than any other of the tree-fruits, and since plums can be grafted on several stocks, each having its own adaptation to soils, the adaptability of the genus is still further increased. Yet the several species have somewhat decided soil preferences.

The Domesticas and Insititias, the plums now almost exclusively grown in New York, grow most satisfactorily, all things considered, on rich clay loams. The plum orchards in this State on such soils contain the largest and most productive trees and produce the choicest fruit from[114] the standpoints of size, appearance and quality. Yet there are exceptions in which exceedingly fine Domestica plums are grown on light loams. The Station collection of about two hundred varieties of European plums is on stiff clay, but well drained, and the results are uniformly good. The Americanas and Nigras grow very well on much the same soils as the European sorts, speaking from the experience on the grounds of this Station, for varieties of these species are not generally grown in New York. Beyond question the Triflora plums, next most widely grown in New York after the Domesticas, are giving the best results on light soils—those most favorable for the peach. The ideal soil for this species is a sandy or gravelly loam but they are growing well on soils having either more sand or more clay than the ideal types. The Hortulana and Munsoniana plums incline to the comparatively light types of soils named as being best for the Trifloras rather than to the heavier lands on which the European plums are most commonly grown.

Plum-growers are well aware of the necessity of good drainage for this fruit but few seem to realize the importance of warmth in a plum soil. The plum, in common with all stone-fruits, grows best, as a rule, on soils having the power to absorb and retain heat, or if the soil have not these properties the location and the cultivation should be such as to provide as far as possible for “bottom heat.”

STOCKS AND PROPAGATION.

A discussion of stocks naturally follows one of soils, for the two are intimately related. The plum can be successfully grown on various stocks and for this reason the practices of nurserymen are diverse, depending upon the cost of the stocks, the ease with which they may be budded or grafted and the adaptability of the tree to the stocks. Unfortunately there is little experimental data to show which of the several stocks is best for the different plums and since growers seldom know what stocks their plums are growing upon they can give almost no information as to the desirability of propagating on this stock or that. Nurserymen know the stocks best adapted to their purpose and from them we have sought information.

A letter of inquiry sent to representative nurserymen in all parts of the United States as to the relative merits of the several stocks for the different species of plums shows that plum propagators in different regions use somewhat different stocks. In New England and the North Atlantic[115] States, the Myrobalan seems to be almost the universal choice, the exception being a few propagators who claim that the Japanese sorts should be worked on the peach, especially for sandy soils, and a few others who are using Americana stocks for the American species.

In the Atlantic states south of Pennsylvania and in the Gulf states to the Mississippi the preferences are very diverse, with the majority of the nurserymen in this region favoring the peach, Myrobalan following as a close second choice. For light soils it would seem that the peach is always to be preferred for this great region. The opinions expressed by the veteran plum-grower, J. W. Kerr of Denton, Maryland, on this subject are worth printing in full. He says:

In the interior region between the Atlantic and Gulf States and the Mississippi, the Myrobalan is used almost exclusively for the European plums and most largely for the other species. Several nurserymen from this region, however, state that the St. Julien is better than the Myrobalan for the Domesticas and Insititias but object to them because the stocks cannot be obtained as cheaply. The peach is generally recommended for the Triflora sorts and the statement is several times repeated that the Americanas would be preferred for the native species if stocks of this species could be obtained readily.

In the northern states of the Mississippi Valley, all nurserymen agree that plums must be worked on Americana stocks. In this region the hardy natives only are grown.

South of the northern tier in the states of the plains the Myrobalan is used almost exclusively for the European species, most largely for the Trifloras, with the peach second for this species, and Americana stocks for the native species. Stark Brothers of Louisiana, Missouri, large growers[116] of nursery stock in this region, express the opinion that “the right stock for native plums is yet to be found.” In Oklahoma, Texas and New Mexico the Marianna is mentioned by several nurserymen as desirable, and is, from these statements, rather more commonly used for stocks in these states at present than in any other region.

On the Pacific Coast propagators use Myrobalan and peach in about equal quantities—the first named for heavy soils and the last for the lighter soils. The native plums are not grown in this region. The almond is mentioned as being desirable in California under some conditions. Some plum-growers in the states of the Pacific propagate their own trees from suckers.

The information given by nurserymen shows that by far the greatest number of plums in the country are grown on Myrobalan stocks. In New York this stock is used almost exclusively. In Europe the writer found that the nurserymen hold that this is a dwarfing stock, and that the trees on it are shorter-lived than on some other stocks. In the nurseries in New York, plums in general, but more especially the Europeans, are larger and finer trees at two years, the selling age, grown on Myrobalan roots than trees grown on other stocks. Nurserymen lodge but two complaints against it; these are that in the South it suckers badly and in the cold states of the Great Plains the roots are killed by the winters. Its advantages from the tree-growers’ standpoint are: Cheapness of the stock, which is usually imported from France, large handsome trees in the nursery, ease of budding and a good union with nearly all varieties. Some growers complain that certain varieties overgrow this stock making in the end a badly mal-formed trunk. The Myrobalan plums are very variable, a fact which finds record in nearly all the characters of tree and fruit and this is somewhat against it as a stock. It is for this reason that there are so many “true” and “false” Myrobalans among nurserymen. Many importers hold that this stock is grown in France from cuttings. Such it seems was the old practice but now, if information from France is correct, most of these stocks are grown from seed. Hansen reports that in South Dakota this stock is worthless because it winter-kills. He says[150] “in experiments at this Station a very small per cent. of Myrobalan stocks survived the first winter and these died the ensuing summer.” It is likely that this stock would suffer in the coldest parts of New York.

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In this region the St. Julien is probably the next most common stock in plum orchards though trees on it are for most part old, as its use is on the decrease. There is a wide-spread opinion among plum-growers that this is a much better stock for Domestica and Insititia plums than any other. On St. Julien stocks varieties of these species, it is claimed, with much to substantiate the claim, produce trees that are longer-lived, thriftier, hardier, deeper feeders, sprout less and are less susceptible to changes in soils. The chief objections to this stock are: It is more expensive, sometimes scarcely obtainable in France; difficult to bud; the young trees do not make as good growth as on the Myrobalan stocks; and the yearlings are much more susceptible to fungi while in the nursery row, though the latter troubles can be remedied wholly or in part by spraying. Hansen, in the reference given above, says that “the St. Julien and European Sloe (Prunus spinosa) both winter-killed” in South Dakota when used as stocks. The St. Julien stock is propagated from layers when properly grown in France[151] but much undesirable stock is now raised from seed. There are fruiting trees of this stock about the nurseries in the neighborhood of this Station which show it to be an Insititia of the Damson type, a type likely to come fairly true to seed yet not sufficiently so as to make seed-grown trees desirable.

The Horse plum was formerly used as a stock by nurserymen a great deal but is now wholly superseded. Indeed, it is so nearly lost to the trade as to make it almost impossible to really know what the plum of this name is. Some describe it as a small-fruited Domestica, others as an Insititia similar to the St. Julien, but the majority of the trees shown by old nurserymen in the nursery region of New York, about the only place in which the stock was used, show it to be a Cerasifera but not Myrobalan. Some of the named varieties of Cerasifera probably sprung from sprouts of this stock. It seems to have had no qualities which would make it worth while to attempt to re-establish the stock.

The testimony of a large number of nurserymen is in favor of the peach as a stock for plums. Budded on the peach, plums of many varieties are grown very successfully on the warm sandy and gravelly soils so well suited to the peach. This stock enables the tree to make a quick growth and come into bearing early, and the roots do not produce sprouts. The budding with the peach is easily done, the young trees make a vigorous[118] growth in the nursery and plums on peach roots can probably be grown at a less cost than on any other stock. Triflora plums in particular make excellent trees worked upon peach stock, the roots are as hardy as the tops and the union is sufficiently congenial to make the resulting tree long-lived. For the Domestica and Insititia plums the peach stock is not so valuable, for with some varieties a good union is not secured and the roots are less hardy than the tops. Among the varieties which nurserymen say will not unite with the peach are: Lombard, Damsons, Yellow Egg and Washington. Peach borers are sometimes troublesome when plums are budded on peach stocks.

Mr. Kerr, in his statement regarding stocks, on page 115, says that it is his practice to whip-graft the plum on “whole-root” peach roots obtaining eventually the plum on its own roots. This method is certainly well adapted to Mr. Kerr’s conditions but whether it would do in heavier soils and a colder climate is doubtful. One would suspect that some varieties of Domesticas and Insititias at least would sprout badly.

In the South, more particularly Texas and the Southwest, Marianna stocks find favor, though their use seems to be on the decrease. The advantages of this stock are such as appeal to the nurserymen rather than to the plum-grower. These are that the Marianna readily strikes root from cuttings and the growth in the nursery is all that can be desired. Cuttings strike more easily in the South than in the North, hence its popularity in the first named region.

For the colder parts of the Great Plains and as far east as to include Wisconsin, Americana seedlings are the only stocks that will withstand the winter. In this region Americana stocks are, of course, used only for the native plums and data seem to be lacking as to whether other plums cultivated for their fruit could be grown on this stock or not. The W. & T. Smith Company of Geneva report that they are now using Americana seedlings for native plums for their eastern trade, speaking of them as follows: “We think we get a larger growth and a better root system by using the native (Americana) stocks. We also consider that the Flowering Almonds, Prunus triloba and Prunus pissardi, make a better growth on native stocks.” From the last statement one would suspect that it would be feasible to grow other orchard plums than the native species on this stock. As yet Americana seedlings are expensive, and until they cost less their use in competition with the Myrobalan and peach stocks will be almost precluded. The chief fault of the Americana stock is that the trees sucker rather badly.

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Besides the plants discussed above various nondescript members of the genus Prunus are used as stocks for cultivated plums under particular circumstances or for particular purposes. Seedlings of Munsoniana plums are supposed to be preeminently adapted for low wet lands. J. W. Kerr believes that seedlings of Prunus hortulana are excellent stocks for native plums as they never sucker.[152] The Sand plum (Prunus angustifolia watsoni) offers possibilities as a stock for dwarfing larger growing species. According to Hansen,[153] who reviews the literature and describes several experiments of his own, the western Sand cherry (Prunus besseyi) dwarfs varieties worked upon it and has the merits of being extremely hardy and of producing trees which bear early and abundantly. As stated in the discussion of Subcordata, stocks of this plum have been used on the Pacific Coast and discarded because it dwarfs trees and suckers badly. According to Wickson,[154] the apricot and almond are sometimes used as stocks for plums in California and in some instances with considerable success.

Lastly, suckers are not uncommonly used by plum-growers for certain varieties. Thus in the western part of New York, the plum-growing region of the East, several varieties as the Reine Claudes and some of the Damsons are propagated from sprouts taken from the base of old trees. This method can be used, of course, only when the trees are grown upon their own roots. The writer was told by plum-growers in Germany and France that most of the plums in gardens and small plantations, constituting the majority of the plums in the two countries, were propagated from suckers. This method has small merit except that it enables a grower to get a few trees cheaply and perhaps gives a better tree of some varieties for a heavy soil. Beyond question it gives trees with a tendency to sucker—an undesirable attribute.

In the horticultural literature of the time recommendations for top-working plums are rather frequent. It is true that many varieties of plums grow slowly and make crooked growths, especially in the nursery, but in the attempts at grafting in New York the failures are more conspicuous than the successes. If top-working is decided upon, the earlier in the life of the tree it is done, the better. For the Domesticas at least, the Lombard is probably the best stock. The method of top-working[120] is to graft in early spring or bud in late summer. Grafting ought to be used more often than it is to renew the tops of injured trees, as the difficulties in doing this are not much greater than in the case of apples.

PLUM ORCHARDS AND THEIR CARE.

Plum trees in New York are set from twelve to twenty feet apart. The amount of room given seems to depend mostly upon the custom in the locality, though, as all agree, it should depend upon the soil and the variety. The deduction which plum-growers are drawing from these experiences is that the plum should have more room than is generally given it, therefore, wider plantings are more the rule now than formerly. Little attention has been paid to mixed planting for cross-pollination in this State, as the Domesticas are planted almost exclusively and seem under orchard conditions to be self-fertile.

In this region plum trees are usually planted two years from the bud, the exception being the Japanese which are sometimes set at a year from the bud. Plum trees in the past have been headed at three or four feet above the ground but the tendency now is to head them lower—half the above distances, and in orchards so planted there seems to be no inconvenience in tilling with modern implements. In the commercial orchards of the State the heads are formed of four or five main branches and in the case of the Domesticas and Insititias about a central trunk but with the Trifloras the leader is often removed leaving a vase-formed head. After the head is formed the subsequent pruning is simple, consisting of cutting out injured and crossed branches and heading-in long, whip-like growths. The Trifloras receive more pruning than the European varieties, as much of the fruit is borne on the growth of the previous season and it is necessary to keep the bearing wood near the trunk. It is the custom to cut rank growing Trifloras severely but the value of such a procedure is doubtful, as the more such a plum is pruned the more it will need pruning in the years to follow. A better plan seems to be to curtail the food and prune as little as possible, though on rich soils the tree would probably grow out of all bounds unless cut back somewhat year after year.

About the only cultivated native plums to be found in New York, if a few Wild Goose trees here and there are excepted, are on the grounds of this Station. Experience here demonstrates that, prune as you will, certain varieties of the native species will remain crooked, ungainly and unkempt. Pruning some varieties is necessary in order to permit pickers[121] to get into the dense, thorny heads; heading-in such varieties would make their tops wholly impenetrable.

In common with all tree-fruits the best plum orchards are tilled. Such tillage usually consists of plowing in the spring followed by frequent cultivation until the middle of August, at which time a cover-crop of clover, oats or barley is sown. The plum seems to require more water than other tree-fruits—it often thrives in comparatively moist land and fails on sandy soils where the peach would grow luxuriantly. Cultivation to save moisture is very necessary for the plum in the experience of New York growers. Grass and grain have proved ruinous in most orchards where tried, though cultivated crops between young trees to pay for keep until fruiting-time are very generally planted. The claim is made by some, and with a show of reason, that there is less of the brown-rot in tilled orchards than in neglected ones for the reason that the mummied fruits which carry the fungus through the winter are buried by plowing and with shallow cultivation, at least, do not come to light and life.

Plum-growers very generally recognize the several distinct and valuable purposes which cover-crops serve in orchards. They protect the tree from root-killing, from cold, keep the soil from washing, add humus and, with legumes, nitrogen to the soil, modify the physical structure of the soil and hasten seasonal maturity of the tree. There is one other function which is not so often taken into account. Plum orchards in which cover-crops are regularly grown, even though the crop be not a legume, need less fertilizers than those in which no such crop is grown. There are several reasonable suppositions as to why there should be such an effect, but one not usually given sufficient consideration is that cover-crops make available much plant food in the soil. Each plant in the crop collects food from soil and air, most of it otherwise unavailable, and turns it over to the trees.

A discussion of fertilizers naturally follows. Present practices in the use of fertilizers with the plum, as with other fruits, are very diverse. It is impossible to ascertain what considerations have governed the applications of fertilizers in the plum orchards of New York or what the results have been. Too often, it is to be feared, fertilizers have been used as “cure-alls” for any or all of the ills to which trees are heirs. Out of the mass of conflicting data as to the effects of fertilizers on plums, the most apparent fact is that much of the fertilizers for this fruit is wasted; this in face of the fact that plums want rich soils. But the plum crop is mostly water, the foliage remains on the ground, the trees grow several years before[122] fruiting, their growing season is from early spring until late fall, the roots go deep and spread far, the trees transpire large amounts of water, hence may thrive on diluted solutions of plant food, and now and then there is an off year in bearing for the trees to recuperate.

It does not follow from the above consideration that plums never need fertilizers, but it does seem plain that they need rather less than truck or farm crops and that applications of plant food must be made with exceedingly great care if fertilizing is to be done without waste. There is a growing disposition on the part of plum-growers to experiment very carefully and know that they are getting the worth of their money before using any considerable quantity of fertilizers for their trees.

Thinning the fruit should be a regular practice with plum-growers, but it is the operation in the growing of this fruit about which growers are most careless both as to whether it is done at all and in the manner of doing. Many growers in New York, realizing the great necessity of thinning certain varieties of Triflora, as Burbank and Abundance, follow the practice very regularly with plums of this group; but the Domesticas are seldom well thinned, though some of them, of which Lombard is a conspicuous example, ought nearly always to have anywhere from one-fifth to half of the fruit removed. Growers of some of the native varieties in regions where these sorts are grown say that under cultivation some kinds of these plums will bear themselves to death if a part of the crop be not removed in most years. Those growers in New York who thin, do the work as soon as possible after the June drop has taken place.

HARVESTING AND MARKETING.

Plum trees in this climate begin to bear when set from three to five years. The Triflora varieties will bear soonest, the Old World varieties next in order, say at four years from setting, and the native sorts, as a rule, come in bearing last. At eight or ten years of age, prolific varieties of the Triflora and Domestica sorts bear in a good year about three bushels of fruit; the Insititia and native varieties, on the Station grounds, at least, do not bear as much, though most of the plums of these two groups bear more regularly than the first named groups.

Plums in this State, and east of the Mississippi generally, are picked and put upon the market just before they reach edible condition; while farther away they must be picked much greener. It is the practice in the East to pick while still somewhat green because the fruit so[123] picked is best handled at this stage of maturity and the brown-rot fungus is likely to destroy much of the crop if left until fully matured. Some of the Triflora sorts, Abundance, Burbank and October, for example, are picked from a week to ten days before ripe and yet develop very good color and flavor. The Domesticas need not be, and are not, picked quite so green. In picking, great diversity exists as to ladders, receptacles, and manner of conveyance from orchard to packing house. These need not be discussed here, nor need the methods of picking be spoken of further than to say that while good growers consider it vital not to bruise the fruit nor destroy the delicate bloom, if such injuries can be avoided, pickers in general are not nearly as observant of these important details as they should be.

The plum crop is sent to market, for most part in New York, in six, eight and ten-pound grape baskets with the preference at present for the smallest of these baskets. Occasionally some fruit is packed in four pound baskets. Rarely, and always to the disadvantage of both producer and consumer, plums go to market in the packages in which the fruit is picked. Indeed, it is seldom advantageous to pack the fruit in the field, it being far better to convey it to the packing house where the preparations for shipping may be more carefully made, as the package and the manner of packing advertise the product. Plums coming to this State from the far West are often wrapped individually in tissue paper as a help in safe shipping and to add to their attractiveness but the fruit grown in the State is seldom, if ever, so treated, though it is possible that choice specimens could be profitably wrapped. Of the sorting, grading, facing and marking the packages, little need be said except that they are too rarely well done in present methods, though there is a steady improvement in attending to these important matters.

Few plums are stored longer than a week at most in common storage and three weeks or a month is quite the limit for most varieties in cold storage. Late plums and in particular some of the prunes might well be stored longer than is now the custom if proper precautions are taken, as is shown by the experience at this Station where a considerable number of the Domestica and Insititia varieties are annually kept in common storage for a month or longer without unusual precautions. Some of the new varieties offered to growers, as Apple and Occident, are recommended as keeping for several weeks after picking. There is a most marked difference in the keeping qualities of this fruit and it is certain that varieties[124] can now be selected for long keeping and that there is a fine opportunity for breeding sorts that will keep even longer than any we now have.

Marketing, the actual selling, is a business quite by itself, and since it is one which has changed greatly in the past few years and is destined to change even more in the near future, a few observations on the subject are worth putting on record. A well developed local market is undoubtedly the best selling place for the plum producer, as in it the sales are directly to the consumer, eliminating expensive middlemen. The westward spread of manufacturing industries, the workers in which use up the western-grown fruit, is making better local markets for eastern plums, a point worth noting, for many New York plum-growers have ceased planting, indeed have been removing trees, fearing western competition.

By far the greater part of the plum crop now finds its way to consumers through the following costly distributive system: 1st. Local buyers who ship to centers of consumption. 2nd. Transportation companies. 3rd. Commission companies who collect and distribute the crop in consuming centers. 4th. Retailers who parcel out the quantities and the qualities demanded by the consumer. The great defect in handling the crop is, that there are too many men and too much machinery to do the work cheaply—moreover, the risks of depreciation are great, and the fruit is not handled on a large scale chiefly because of a lack of capital by the grower or local buyer. These defects in the present distribution of plums in New York make the price received by the grower about half that paid by the consumer and the selling of the crop a more or less speculative business. The plum industry, as is the case with all fruits, is greatly hampered by the present marketing systems.

Unfortunately there is yet but a small outlet for surplus plums as manufactured products. As a rule the commercial outlook is best for those fruits of which the surplus can be turned into by-products. The only outlet for the plum in the East is in canning, as this region is unable to compete with the West in the making of prunes[155] and as the several[125] plum products of the Old World are not in demand in the New World. Beyond question there are a number of products, as preserves, jellies from the native plums, glacé fruits, plum butter, marmalades and the like, which could be made profitable for the markets and thus a great help in utilizing surplus plums.

DISEASES.

Plums are subject to a considerable number of fungus diseases, several of which are often virulent, the virulence depending on locality, season, weather and variety. Happily for the plum industry, knowledge of plant pathology has made such advancements in recent years that nearly all of the diseases of this fruit are now controlled by preventive or remedial measures.

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One of the commonest and most striking of the diseases of the plum is black-knot[156] (Plowrightia morbosa (Schw.) Saccardo) characterized by wartlike excrescences on shoots and branches. In early summer these knots are dark green, soft and velvety, but as the fungus ripens in the fall the color changes to a carbon-like black and the knots become hard and brittle. The disease is usually confined to one side of the twig or branch so that death of the affected part does not ensue at once. Black-knot is an American malady, at one time confined to the eastern part of the continent where in some localities its ravages forced the abandonment of plum-growing. The fungus is now endemic to wild or cultivated plants in practically all the plum-growing regions of the continent, but it is still epidemic only in the East, the South and West being practically free from the disease. Unless especially virulent black-knot is controlled by cutting out the diseased wood. Usually eradication is not possible without several prunings during a season.

Much has been made of the supposed immunity of some varieties of plums to black-knot. In the vicinity of this Station, where the disease is always present and often rampant, the differences in immunity are not very marked in varieties of the same species. The Trifloras are less attacked,[127] however, than any other group of plums, and the Insititias rank next in immunity. No variety of the Domesticas has yet proved to be free from the disease but strong claims are made that Middleburg and Palatine are relatively free.

Next in order of seriousness among the diseases which attack cultivated plums is the brown-rot[157] (Sclerotinia fructigena (Persoon) Schroeter) known also very commonly as the ripe-rot and sometimes as peach-blight. The disease is most conspicuous on the ripe fruits of the various drupes and is popularly supposed to be confined to the fruits alone. Such is not the case, for it also attacks, and very vigorously oftentimes, the flowers and shoots. The presence of the disease on the fruits is known by a dark discoloration of the skin which is afterward partly or wholly covered by pustule-like aggregations of grayish spores. The decayed fruits may fall to the ground, or as is more usual in the case of plums, they hang to the tree and as the juice evaporates become shriveled mummies, each mummy being a storehouse of the fungus from which infection spreads the following season. The twigs, flowers and leaves are known to be suffering from inroads of the parasite when they are blackened as if nipped by frost. In warm, damp weather the rot spreads with great rapidity and fruits touching in clusters or in boxes stored for shipping are well placed to spread the epidemic. Destruction of the mummy-like fruits and all other sources of infection, and spraying with bordeaux mixture are now practiced as preventives, but so far as the crop is concerned with but indifferent success. A better remedy than we now have is eagerly looked for by growers of fruits.

The hosts of this fungus show varying degrees of susceptibility to it, the peach and the sweet cherries being more subject to it than plums. Similarly, among plums some species and varieties are more susceptible than others. Thus the Trifloras and Americanas, the latter especially in the South, are injured more by the brown-rot than other species. The idiosyncrasies of varieties in this regard are best shown in the discussions of the individual sorts.

Several interesting and sometimes destructive diseases of plums are caused by various species of the fungal genus Exoascus.[158] The most common of these, and the most striking and destructive, is plum-pockets (Exoascus[128] pruni Fuckel), which causes prominent deformities of the fruit. These give the disease the common name or less frequently “bladders” and “curl.” The fungus attacks the developing fruits at an early stage of their growth and causes the production of a spongy mass in the fleshy tissue which greatly enlarges and distorts the plum. The stone in a diseased plum is but rudimentary or very often not at all developed. Less prominently but quite as frequently, the leaves are attacked, showing as they unfold more or less red or yellow with a very decided curling and arching of the leaf-blade. The disease usually spreads from the leaves to the shoots, the infected shoots with their rosettes of mal-formed leaves giving the tree a most unsightly appearance. Prevention at present consists of removing the diseased parts and spraying with bordeaux mixture when the buds begin to swell. Munsoniana and Hortulana plums seem to be most susceptible to this disease. Atkinson[159] has described several species of Exoascus on the different species of wild plums, some of which are liable to be found on the cultivated varieties of the native plums. They are all very similar to Exoascus pruni, differing chiefly, in the eyes of the layman, in forming smaller pockets. Sturgis[160] records an attack of one of the leaf-curl fungi, distinct from the plum-pockets fungus, on varieties of Triflora in Connecticut, which seemed to him to be of scientific and economic importance.

The leaves of the different species of cultivated plums are attacked by several fungi which produce diseased spots on the foliage, which for most part drop out, causing a shot-hole effect. These diseases pass under such descriptive names as “shot-hole fungus,” “leaf-spot,” and “leaf-blight.” The fungus probably responsible for most of this trouble is best known as the shot-hole fungus[161] (Cylindrosporium padi Karsten). The Domestica and Triflora varieties are very susceptible to this fungus, which, on the foliage of the first, causes spots for most part, while on the latter the spots on the leaves are nearly always followed by holes. Varieties of the native species, especially those of Americana and Nigra, are relatively free from this disease. Another of these shot-hole fungi is Cercospora circumscissa Saccardo[162], much less common than the former, but still to be considered and especially on the foliage of Americana. All of these diseases[129] of the foliage are prevented to some degree by the proper use of bordeaux mixture, which, on the Triflora plums at least, must be used with great care to avoid injury. Cultivation has a salutary effect as it destroys the diseased leaves which harbor the fungi.

Another disease of plum foliage, occurring rarely on the fruit, is the plum-leaf rust[163] (Puccinia pruni-spinosae Persoon) which produces so considerable a number of spore cases on the underside of the leaves as to give the foliage a brownish cast and to cause defoliation in severe infections. The fungus is most apparent in the fall and most troublesome in warm, moist climates. Bordeaux is used as a preventive.

Stewart and Rolfs have shown that trunks and branches of plums affected by sunscald in New York are almost invariably infested by a fungus[164] (Valsa leucostoma Persoon) which in the Old World is known as the “die back” of the peach. The disease manifests itself on plums chiefly by affected areas much depressed at the boundary between the living and the dead bark, these areas usually, not always, having connection with sunscald injuries on the trunk. The disease is accompanied by more or less gumming.

In common with nearly all rosaceous plants, in nearly all countries, the plum is sometimes seriously injured by the powdery mildew[165] (Podosphaera oxyacanthae DeBary). The affected leaves have a grayish appearance caused by the parts of the fungus which project beyond the leaf tissue; when badly diseased the leaves are more or less arched and curled. Mildew is seldom prevalent enough on plums to require treatment.

The crown gall,[166] (Bacterium tumefaciens Smith and Townsend) is a parasite on all of the fruits of the order Rosaceae and is especially common on nursery stock, attacking plums in many soils but rarely, however, to the great injury of the plant. These galls are perennial structures of very varying duration. They are to be found on the roots, usually at the collar of the plant, and vary from the size of a pea to that of a man’s fist, forming at maturity, rough, knotty, dark-colored masses. Means of[130] prevention or cure are not established though all agree that soils may be inoculated with the disease from infected stock; hence the necessity of discarding diseased trees at transplanting time.

Smith found in Michigan and Clinton in Connecticut a disease of the fruit called bacterial black spot[167] (Pseudomonas pruni Smith) of the same generic origin as the crown gall but widely different in nature. The writers and the growers who found the infected fruit, saw the disease only on the Triflora plums. It attacks the green fruits which show conspicuous, black-purple, sunken spots sometimes as large as half an inch in diameter. The injuries are usually isolated and quite superficial but nevertheless, spoil the fruit.

The plum in common with other stone-fruits often suffers from an excessive flow of gum, for which trouble the name gummosis[168] is now generally applied. The disease is to be found wherever plums are grown but it is much more destructive on the Pacific than on the Atlantic seaboard. So far as is now known gummosis is secondary to injuries caused by fungi, bacteria, insects, frost, sunscald, and mechanical agencies. The disease is least common in species and varieties having hard wood; on trees on soils favoring the maturity of wood; under conditions where sun and frost are not injurious; and, obviously, in orchards where by good care the primary causes of gumming are kept out. Stewart[169] has recorded an interesting case of gum-pockets in the fruit, but could assign no cause.

Mechanical injuries from the sun, frost and hail are troubles with which nearly all plum-growers must contend at one time or another. In this region the Reine Claude and Triflora plums suffer much from sunscald but none are wholly immune, though Lombard is possibly most so. These injuries from the elements of weather are often mistaken for diseases, and are so often followed by fungal parasites and insects as to make it difficult to distinguish the primary from the secondary trouble. Low-heading of the trees is the best preventive of these trunk injuries.

Plums are somewhat subject to attacks of the well-known peach scab[170] (Cladosporium carpophilum Thumen). The scab appears in numerous, small, sooty, circular spots of brownish color, often confined to one[131] side of a fruit but in other cases distributed over the whole surface. None of the cultivated species are free from the disease but the Munsoniana, and Hortulana varieties are most susceptible to it. Pear blight,[171] (Bacillus amylovorus (Burrill) DeToni) commonly thought of as a disease of the pear and apple has been found on various plums, and the yellows of the peach, cause unknown, is often quite destructive to Triflora plums. According to Smith the peach rosette,[172] cause unknown, attacks both wild and cultivated plums in the South and is quickly fatal. The disease was prevalent on the wild Angustifolias, on two varieties of Triflora, Kelsey and Botan, but the observer had not seen rosette on varieties of Domestica.

Waugh describes a trouble which he calls “flyspeck fungus”[173] found on fruits sent from the Southern States, in which small areas are thickly dotted with black spots; also a fruit-spot on plums from Texas caused, as he states, by an undetermined Phoma.[174] Starnes of Georgia describes a malady of the Triflora plums called “wilt,”[175] cause unknown, which he states is the most serious obstacle to the culture of this plum in the South. In this peculiar disease the foliage passes directly from a green, healthy state into a wilted and then parched condition, the death warrant being signed when a tree is once affected. In Oregon and Washington the Italian Prune is subject to a leaf-curl[176] which begins in mid-summer and curls the leaves conduplicately without withering but shriveling somewhat. As the season advances the leaves turn yellow and many of them drop. Neither cause nor cure is known. Smith described a plum-blight[177] of native plums in Georgia which “destroys large branches or even whole trees in mid-summer in the course of a few weeks.”

INSECTS.

Cultivated plums furnish food for a great number of insects. Many of the destructive insect pests of the several cultivated species of Prunus are known to have come from the wild plants of the genus, but others, and possibly the majority, come from over the seas. No less than forty[132] species of insects may be enumerated as pests of the plum and many more can be counted as occasional parasites on one or another of the species. Of the formidable pests the plum curculio is probably the most troublesome. The plum curculio[178] (Conotrachelus nenuphar Herbst) is a rough, grayish snout-beetle somewhat less than a quarter of an inch in length, an insect so familiar to fruit-growers as hardly to need a description. The female beetle pierces the skin of the young plums and places an egg in the puncture. About this cavity she gouges out a crescent-shaped trench, the puncture and trench making the “star and crescent” of the Ottoman Empire, hence the common name of the beetle, “The Little Turk.” The egg-laying process may be repeated in a number of fruits and from each egg a larva hatches within a week and burrows to the stone, making a wormy fruit. Most of the infested plums drop. In years past plum-growers relied upon jarring the beetles from the trees in the early morning, but the treatment was too expensive, and poisoning with an arsenate is now the chief means of combating the pest. Rubbish and vegetation offer hiding places for the insects and hence cultivated orchards are more free from curculio. Thin skinned varieties are damaged most by the insect but there are no “curculio-proof” plums.

A larger snout-beetle than the curculio, the plum gouger[179] (Anthonomus scutellaris LeConte), occasionally does much damage to plums. The work of the gouger may be told from that of the curculio by the absence of the crescent cut about the puncture made for the egg, and from the fact that the larvæ of this pest chiefly infest the stone and those of the other insect the flesh of the plum. The remedies are the same for the two insects though the gouger is more easily destroyed.

Among the several borers which are more or less destructive to species of Rosaceae only the peach borer[180] (Sanninoidea exitiosa Say.) may be counted as a troublesome pest of the plum. The larvæ of this insect are frequently to be found in both wild and cultivated plum trees and must be combated in nearly all plum orchards east of the Rocky Mountains. The prevention of the work of the borer is best accomplished by thorough cultivation, the use of coverings of tar and poisonous washes and mounding the trees. Destruction is effectively carried out only by digging out the borer with knife or wire. The lesser peach borer[181] (Sesia pictipes Grote[133] & Robinson) attacks the plum and in New York has been found particularly injurious to the Wickson plums. The flat-headed apple tree borer[182] (Chrysobothris femorata Fabricius) is frequently found in the wood of wild plums and is sometimes a pest of the several cultivated species. It is treated as is the peach borer. The shot-hole borer[183] (Eccoptogaster rugulosus Ratzeburg) a diminutive insect which deposits its eggs in the trunks or large branches of various members of the genus Prunus, may be regarded as an effect rather than a cause of disease, for it seldom injures perfectly healthy plum trees. The peach bark-beetle[184] (Phlœotribus liminaris Harris) is somewhat similar in its work to the shot-hole borer and like it is found for most part only in diseased and decrepit trees.

The plum aphis[185] (Aphis prunifolii Fitch) is sometimes very destructive to varieties of the native plums, especially the Americanas, and occasionally injures or even kills the young trees of the Domestica sorts. It is not a formidable foe in New York, and it is the exception when trees must be treated for it, the treatment being any of the contact solutions used against sucking insects. The cherry aphis[186] (Myzus cerasi Linnaeus) and the green peach aphis[187] (Myzus persicæ Sulzer) are much less common than the plum aphis on plum trees, but are sometimes abundant on foliage of this fruit and are combated in the same way as the more common aphis. Gillette enumerates two other aphids as attacking the plum in Colorado—the rusty brown plum louse[188] (Aphis setariæ Thomas) and the mealy plum louse[189] (Hyalopterus arundinis Fabricius).

Several scale insects infest the plum. Chief of these is the dreaded San José scale[190] (Aspidiotus perniciosus Comstock) known and feared by all fruit-growers in the United States. The lime and sulphur solution is now the most common and probably the most effective spray for this insect. The European fruit lecanium[191] (Lecanium corni Bouche) occasionally does a great deal of damage in New York and now and then destroys the whole crop in an orchard. The winter treatment for San José [134]scale is used to control this pest, but usually such treatment is supplemented by a summer spray about July first with such contact sprays as whale oil soap and kerosene emulsion. Of the other scales[192] which feed upon plums and now and then become pestiferous the following may be named: The fruit pulvinaria (Pulvinaria amygdali Cockerell), the mealy bug (Pseudococcus longispinus Targioni), the scurfy scale (Chionaspis furfura Fitch.), the West Indian peach scale (Aulacaspis pentagona Targioni), the Putnam scale (Aspidiotus ancylus Putnam), the cherry scale (Aspidiotus forbesi Johnson), the walnut scale (Aspidiotus juglans-regiæ Comstock), Howard’s scale (Aspidiotus howardii Cockerell), the European fruit scale (Aspidiotus ostreæformis Curtis), the red scale of California (Chrysomphalus aurantii Maskell), the oyster-shell scale (Lepidosaphes ulmi Linnaeus), and the soft scale (Coccus hesperidum Linnaeus).

Wild plums of several species seem to be favorite feeding grounds for the tent caterpillar[193] (Malacosoma americana Fabricius), but cultivated plums are not so often attacked; the spraying with arsenites usually given for the curculio is fatal to this pest as well. The spring canker-worm[194] (Paleacrita vernata Peck) and the fall canker-worm[195] (Alsophila pometaria Harris) are other caterpillars which often do much damage unless checked by destructive measures, of which the best are the arsenical sprays. The larvæ of a considerable number of other moths and butterflies are often found on plum foliage but seldom in such numbers as to require systematic destruction.

The eye-spotted bud-moth[196] (Tmetocera ocellana Schiffermuller) is a rather serious pest in plum nurseries where the larvæ eat into the young buds at the time they are opening, often destroying the shoots. Sometimes the larvæ are found destroying buds on old trees. The arsenical sprays are used to destroy this pest. The peach twig-moth (Anarsia lineatella Zeller) is now and then found in plum twigs but is seldom classed as a plum pest.

The clover mite[197] (Bryobia pratensis Garman) formerly considered a serious pest of the plum only in the far West, is now abundant in plum[135] orchards in New York. It can be controlled by applications of lime and sulphur. The bumble-flower beetle[198] (Euphoria inda Linnaeus) is reported by Goff to be occasionally very injurious to plums in Wisconsin. Remedies seem not to have been tried. The larvæ of the cherry slug[199] (Selandria cerasi Peck) is not infrequently found doing damage to plum foliage and occasionally the larvæ of one or two other saw-flies feed on the plum. These are all overcome by the use of arsenical sprays. At least one of the curious insects know as “case-bearers” attacks the plums. The troublesome one is the pistol case-bearer[200] (Coleophora malivorella Riley), which is not often a pest but has sometimes done considerable damage. Attempts to check this insect with the arsenical sprays have usually proved successful. The plum tree is a host-plant of the hop aphis[201] (Phorodon humuli Schrank). So much does this insect feed on the plum that the destruction of plum trees in the vicinity of hop fields is recommended to hop-growers by Riley.

ABUNDANCE

Prunus triflora

Though Abundance has been in America only a quarter of a century, it is now about as well known as any other plum, being probably the best known of the Triflora plums. The two chief assets which have given the variety its great popularity so quickly are adaptability to a wide diversity of soils and climates and, as its name implies, abundance of fruit, for it bears not only heavily but yearly. As a market plum Abundance has been overplanted since it ships and keeps poorly, is much subject to brown-rot, matures unevenly and drops rather too readily as it ripens. Whether for market or home use, the fruit of this variety should be picked before it is quite ripe as it develops in flavor best when so picked and the dropping and rot are thus avoided to some extent. It is an exceedingly variable plum and undoubtedly several well marked strains could be selected, some of which are not as hardy or otherwise as valuable as others. While Abundance has passed the heyday of its popularity it is still one of the most desirable of the Triflora plums.

This variety was imported from Japan by Luther Burbank in 1884, and was introduced by John T. Lovett, Little Silver, New Jersey, under the name Abundance, in 1888. A large number of Japanese plums that have since been introduced have proved to be either identical or so nearly like the Abundance that much confusion has arisen. Abundance was first known as Botan, but that name was dropped as it refers to a group[137] of plums in Japan rather than to a variety. Babcock, which is said to have been imported by Burbank in 1885 and named for Colonel E. F. Babcock, a nurseryman of Little Rock, Arkansas, has been described by Bailey as indistinguishable from Abundance. Botankio, described in the Georgia Horticultural Society Report for 1889, proved to be the Abundance as tested at the Cornell Experiment Station. The Chase plum, also disseminated in New York under the name Yellow Japan, was bought by the R. G. Chase Company, Geneva, New York, for the Abundance, but as it was thought to blossom and fruit later than that variety, it was distributed as a new plum; in 1897 Bailey considered it the same as Chabot, but in 1899 he stated that it and Abundance were identical. The Douglas plum is also identical. Dr. J. T. Whitaker of Tyler, Texas, imported this variety and introduced it in 1886 under the name of Hytankayo. Bailey, who tested Whitaker’s variety from trees obtained from T. V. Munson, Denison, Texas, found a yellow-fruited strain and to distinguish the purple form named the latter Munson.[202] As this name had been applied to a native plum, R. H. Price, of the Texas Experiment Station, in 1894 renamed the variety calling it Douglas.[203] There have been two types of this Douglas plum disseminated; Bailey, in 1899, found no difference between it and Abundance except that the Douglas seemed to have a little drier flesh; others testing Douglas found it to be identical with the Chabot. Burbank No. 2, imported by Luther Burbank in 1885 and introduced by him in 1889, is very similar if not identical with the Abundance. Oriole, recently introduced by the Texas Nursery Company, Sherman, Texas, is so nearly like Abundance as to be unworthy of a separate name. The American Pomological Society added Abundance to its fruit catalog list in 1897.

AGEN

Prunus domestica

Agen is the plum par excellence for prune-making in France and America. Several qualities make it admirably fit for curing into prunes.[139] To begin with, it has a high percentage of sugars and solids so that the plum cures readily into a firm, sweet, long-keeping prune which in cooking needs comparatively little sugar; again, the trees bear regularly, abundantly and the plums are uniform in size,—productiveness, regular bearing and uniformity of size of fruit being necessary attributes of a good prune-making plum; lastly, it hangs well on the tree as it ripens and afterwards so that the curing really begins on the tree. Besides making most excellent prunes, the Agen is a very good dessert plum—one of the best—and ought to be in every home orchard and, where it attains sufficient size, in every commercial plantation. Lack of size is the defect in this variety which has kept it from being more largely grown outside of prune-making regions. If by pruning, thinning and other cultural treatment the size of the plums could be increased, the Agen should prove a valuable commercial fruit in New York.

The name of this variety is derived from Agen, a region in France where it is extensively grown. Tradition says that on their return from the Crusades, the Benedictine monks brought with them from Turkey or Persia what was then known as the Date plum and planted it in the garden of their abbey on the River Lot, in the vicinity of Bordeaux, France, and that afterwards this became the Agen. Its first recorded importation into the United States was made in 1854 by the United States Patent Office, though it was described by Prince as early as 1832. The most important introduction was made, however, in 1856, when Louis Pellier of San Jose, California, introduced Agen on the Pacific Coast, where it soon became and still is the leading plum, though with curious persistency the fruit-growers there call it the “French Prune” and the “Petite Prune.” In 1862 this variety was added to the fruit catalog list of the American Pomological Society. There are many strains of Agen in America, due to the numerous importations of grafts from various parts of France, where the plum orchards are frequently grown from seedlings or from sprouts; some of these strains are worthy of varietal recognition.

AITKIN

Prunus nigra

Aitkin is very favorably mentioned in the references given above and undoubtedly has value for the Northwest. It was listed in the catalog of the American Pomological Society in 1899. The variety was found growing wild in Aitkin County, Minnesota, by D. C. Hazelton on land adjoining his farm. It seemed to possess merit and was introduced in 1896 by the Jewell Nursery Company of Lake City, Minnesota. Because of having originated near Itasca Lake, it has been confused with the Itasca plum, which preceded it by nearly ten years. The following description is a compilation:

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ALHAMBRA

[Prunus triflora × Prunus cerasifera × Prunus domestica] × [(Prunus simonii × Prunus triflora) × (Prunus americana × Prunus nigra)]

Although it is over a decade since Alhambra was offered to fruit-growers, it has made little headway in popularity and is chiefly of interest because of its breeding. It is not often that we can trace the pedigree of a plant for more than one or at the most two generations, but in Alhambra we are particularly fortunate. Luther Burbank, the originator, began by crossing Kelsey and Pissardi, and the offspring from this cross was fertilized with Agen pollen. This tri-hybrid was in turn fertilized with pollen from a complex hybrid of a cross of Prunus simonii and Prunus triflora pollinated by a cross of Prunus americana and Prunus nigra. As might be expected, the offspring of this final cross was extremely variable and from it was selected the Alhambra. The variety was named by the originator in 1898.

ALTHAM

Prunus domestica

Altham is an excellent plum for dessert or home use. The color is a trifle too dull for market purposes and yet it is better colored than McLaughlin, which sells fairly well. The fruit is the type of the last named[142] plum but is later. In Europe this variety is well known and highly esteemed for its quality, but unfortunately it is almost unknown in America. The variety is well worth trial in this country as a fine plum of the Reine Claude group. Altham is a seedling of Reine Claude, raised by Herr Prochaska, gardener to Count Michael Joseph Althann, of Swoyschitz, in Bohemia. It was noted in the English Journal of Horticulture for 1869 as a new plum sent out by Thomas Rivers.

AMERICA

Prunus munsoniana × Prunus triflora

America is illustrated and described in full chiefly because it is the most promising cross between Prunus munsoniana and Prunus triflora. The fruit of the variety is unusually attractive in appearance, golden-yellow with a red cheek and waxy lustre turning currant-red when ripe, ships exceptionally well and is of very good quality for cooking, but is without merit as a dessert plum. The trees are large, very vigorous, as hardy as either of its parents or possibly more so, and enormously productive. The qualities of fruit and tree are such that the variety ought to succeed in commercial plantations where any but the hardiest native plums are cultivated. America is almost phenomenally free from rot, considering its parentage.

This variety is one of Luther Burbank’s productions, grown from a seed of Robinson fertilized by pollen from Abundance. It was introduced[143] by the originator in 1898 and has been since that time well tested at several places in the eastern states and is very generally well spoken of for a plum of its kind for the East.

AMERICAN

Prunus domestica

American originated with a Mr. Peterson of Elkton, Douglas County, Oregon, as a sprout from an old tree. It has never been extensively disseminated, but seems to be a variety of considerable promise. The fruit as grown on the Station grounds resembles Hand rather closely; is large for a plum of its type, is a handsome golden color, is high in quality and will probably keep and ship well. Too little is known of its tree-characters to recommend it unqualifiedly.

[144]

AMERICAN EAGLE

Prunus americana

Of the origin of this very good Americana variety little is known except that it probably came from Missouri, as it was introduced, in the fall of 1859, by the Osceola Nursery Company, Osceola, Missouri. Although an old variety it was not listed by the American Pomological Society until 1899. In regions where Americana plums are grown, American Eagle ought to be better known, its chief defect being the dull color of the fruit.

AMES

Prunus americana × Prunus triflora

Though Ames has been known to the public scarcely ten years, its good qualities have given it relatively high rank among Americana plums with which it must be compared. Though supposed to be a cross between Prunus americana and Prunus triflora, the variety shows few, if any, traces of the Triflora parentage, except, possibly in the shape and color of the fruit. The variety is distinguished from other Americana plums by reddish[145] dots on the fruit instead of the yellowish dots commonly found on the plums of this species. The fruit of Ames is very attractive in color, the quality is fair, it keeps and ships well and it is fairly free from rot, characters which make it desirable where the native plums are grown.

This variety was produced by Professor J. L. Budd[204] of Ames, Iowa, by crossing De Soto with pollen of a “large Japanese plum received from Oregon.” For a long while it was known as De Soto × Oregon No. 3 and as Japan Hybrid No. 3, but was named Ames by Professor John Craig, now of Cornell University.

APPLE

Prunus triflora ×?

The Apple is a conspicuous plum; its shape, color, size, flavor; its firm, blood-red flesh and long-keeping quality, all distinguish it. Even the tree is marked with its robust growth, flat-topped head, peculiar, light brown bark, handsome foliage and wood that can be propagated from cuttings with surprising ease. It is difficult to predict the future of this interesting plum, but probably it will remain for most part a curiosity. Its peculiar flavor is not pleasant at first taste and it is doubtful if many will learn to like it. Unpalatability is the defect of the variety which will most often be counted against it. In general the Apple is inferior for dessert or kitchen to the Satsuma, itself none too good, which it most nearly resembles of all plums. In the Station collection tree and fruit are quite susceptible to both fungus and insect pests and the fruits ripen unevenly. The fruit of the variety keeps and ships remarkably well and these qualities may be its saving grace, both so well developed as to make it valuable for breeding purposes when these characters are desired.

In his catalog for 1898 Burbank announces the Apple as a new plum and says, “Among the welcome surprises found three years ago among[147] a lot of some twenty-five thousand plum seedlings was this one, bearing a cruel load of enormous plums when only two years old.... It was at once named Apple from the very close resemblance in form, color general appearance, and rare keeping qualities.... Its parentage is not known, except that it is a second generation seedling from cross-bred seedlings, and no doubt Satsuma and probably Robinson are in its line of ancestry.” Satsuma characters are readily detected in tree and fruit and especially its hard, red flesh, but in no way is its descent from Robinson apparent.

APRICOT

Prunus domestica

Since John Parkinson described the “Apricocke” plum in 1629, several types of this variety have appeared in literature and these have become so badly confused that it is impossible to separate them. However, as the variety is nearly extinct, and will probably never be revived, this confusion is happily of historic rather than of economic interest. Nearly all writers recognize at least two types, one of which is superior to the other. The better of these can readily be identified as the “Abricotée” of Duhamel, and should be considered the true Apricot. Little is known of the early history of this variety other than that it was very generally distributed throughout Europe early in the Seventeenth Century. The American Pomological Society rejected Apricot in 1858, though it is doubtful if they had the true type. This variety is not to be confused with the Prunus simonii, commonly called “Apricot,” or the native plum of that name.

ARCH DUKE

Prunus domestica

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Arch Duke ought to become one of the leading plums for the market in New York. The qualities which fit it for a high place among commercial varieties are: large size, handsome color—a rich, dark purple with thick bloom—and firmness of flesh and skin so that it both keeps and ships well. The accompanying color-plate does not do the variety justice, either in beauty, color or size of fruit. Arch Duke compared with Grand Duke, known by all plum-growers, is nearly as large, neck thicker, the same color, bloom heavier, quality higher, flesh firmer, stone free and ripens earlier. The tree-characters, like the fruit-characters, are all good. While this variety is suitable for both home and market use it appears after a thorough test in many parts of the State for nearly twenty years to be especially well adapted for a market fruit.

Arch Duke was raised by Thomas Rivers, Sawbridgeworth, England, from seed of De Montfort, and was sent out in 1883. It was first noted in America by the Ontario Fruit Growers’ Association in 1891 and was imported into the United States by S. D. Willard[205] of Geneva, New York, about 1892.

ARCTIC

Prunus domestica

Arctic is very generally supposed to be preeminent in two qualities, hardiness and productiveness. On the grounds of this Station it is both hardy and productive and from its behavior here it might well be recommended for these qualities, but as to its hardiness elsewhere pomologists do not agree. In the references given above, Downing says it is the hardiest plum known; in Michigan it is reported very tender in the nursery row;[151] a Canadian writer says it is not hardy enough for Canada; and it is reputed in the prairie states to be not hardier than Lombard. The place of its origin, where few plums are grown, and the fact that it is one of but few that can be grown in parts of Canada and New Brunswick establish the claim that it is one of the hardiest of the Domesticas, possibly not more so, however, than Lombard, Voronesh and a few others. The small size and mediocre quality of the fruit and the dwarfish trees should rule Arctic out where less hardy varieties can be grown.

This variety was first noted in 1881 by Downing who says it originated on the grounds of A. T. Moore, Ashland, Maine, about forty miles north of Bangor. The parentage of Arctic is unknown. According to the originator, it was grown from a seed of a medium sized blue plum bought at a fruit-stand in Boston. In 1881 Arctic was added to the American Pomological Society catalog, where it still remains.

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ARKANSAS

Prunus munsoniana

Arkansas, as the synonymy shows, originally, and even now, usually has Lombard as a suffix, but the name is misleading as the plum is in no wise like a Lombard and following the rules of the American Pomological Society it has been dropped in The Plums of New York. On the grounds of this Station, Arkansas is one of the most valuable plums of its species, being unusually attractive in size, color and shape and one of the best in quality of its kind. Its chief fault is a lack of robustness in the tree. While it would not prove profitable as a market plum in New York, it could be well planted in a commercial orchard in regions where native plums must be grown, and in New York it would at least add a pleasing variety to any collection of plums. This variety was brought to notice by T. V. Munson in 1881. It originated in Arkansas and was introduced by J. D. Morrow & Sons of that state.

AUTUMN COMPOTE

Prunus domestica

This plum is well and favorably known in England, but it is scarcely grown in America, though it has much in the character of its fruit at least to recommend it. The plums are attractive in appearance and while not of the highest flavor are yet far above the average in the qualities which make a good dessert fruit, while for culinary purposes it ranks among the best. The trees are productive, hardy and fairly vigorous and may be especially noted as holding their crop well. Autumn Compote is a seedling of Cooper, raised by Thomas Rivers, Sawbridgeworth, England, about 1840.

BARTLETT

Prunus triflora × Prunus simonii

Bartlett was grown by Burbank from a cross of Prunus simonii with Delaware, the latter one of his earliest hybrids. The originator disposed of the variety in 1899 and it immediately became popular with nurserymen and was soon offered for sale in all parts of the United States. Fruit-growers have not received it so well, however, and most of those who have tried it have discarded it or hold the variety as a curiosity. The fruit is attractive in appearance and the Bartlett pear flavor is agreeable, but the skin cracks badly in this State and the flesh is too soft for shipping. The tree with its stiff, upright branches resembles a Lombardy poplar and with its bright, glossy green foliage is an attractive ornamental. It is still further peculiar in bearing thick clusters of flowers at the ends of lateral spurs.

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BASSETT

Prunus maritima

Bassett, the best known of the few cultivated varieties of Prunus maritima, was found growing wild in New Jersey and was turned over to a nurseryman, Wm. F. Bassett of Hamilton, New Jersey, who introduced it in 1872. After its introduction it became somewhat popular in the West, gaining quite a reputation as being “curculio proof,” However, its marked inferiority to varieties of other species, in both size and quality, has now banished it from all commercial plantings. The following description is compiled.

BAVAY

Prunus domestica

Bavay is one of the best of the green plums—a worthy rival in all respects and in some superior to its parent Reine Claude. It is unexcelled as a dessert plum and its delicious flavor is retained in cooking, making the somewhat rare combination of a first rate dessert and a first rate culinary fruit. Bavay is not only satisfactory in the qualities which make it desirable to the consumer but it is a good market plum for it both keeps[156] and ships well. The flavor is not quite equal to that of Reine Claude, one of the best of all plums in quality, but in tree-characters the Bavay surpasses the older variety. The trees bear young, annually and heavily, sometimes too heavily, and while not as hardy, as large, as robust or as long-lived as could be wished, yet in these respects they are superior to those of most of the varieties of Reine Claude plums. Some horticulturists recommend that the Bavay be top-worked on a more vigorous, hardy and longer-lived stock but the behavior of trees so treated in this vicinity makes top-working a very doubtful expedient. Lombard is usually recommended as a stock upon which to work it. Bavay is indispensable in home orchards and can be recommended for much more general planting in commercial orchards.

This variety is a seedling of Reine Claude produced by Major Esperin of Malines, Belgium, about 1832, and dedicated by him in 1843, to M. De Bavay, Director of the Royal Nurseries, at Vilvordes, near Brussels. Though this variety is distinct from its parent in tree-characters, in having a later season, smaller fruit and a different flavor, the two plums have become confused by many nurserymen and horticulturists. In 1856, the American Pomological Society placed Bavay on its fruit catalog list where it still remains.

BEJONNIERES

Prunus insititia

This variety is so highly prized in France that it is here recommended for trial even though the trees as they grow in this part of New York have not been productive. It is too small for a dessert plum but might become of value here if used as in France for tarts, spices, preserves and drying. The plum originated about 1827 in the nursery of Andre Leroy, Béjonnieres, Angers, France.

BELGIAN PURPLE

Prunus domestica

Belgian Purple is a medium grade plum of little value for dessert but rather highly esteemed for culinary purposes, especially in Europe. It probably has but a small place in American pomology. Concerning[158] the origin of the variety, nothing is known although it is generally believed to have originated in Belgium prior to 1850.

BELLE

Prunus domestica

Belle is an unusually large, handsome plum but unfortunately is not of very high quality. It is much like Pond but is brighter red, a little smaller, less necked, the stem is shorter, the apex more blunt and it is more of a clingstone. European authorities say that Belle is second to none for culinary purposes and its handsome appearance gives it value across the seas as a dessert plum. As Belle grows on the grounds of this Station—it seems not to be found elsewhere in New York—the tree-characters are quite above those in the average variety of plums and when considered with the fine, late fruits, indicate that the variety might be grown with profit for market purposes. It well deserves to be tried by commercial plum-growers.

Belle came from Brussels, Belgium, and was propagated by the famous horticulturist, Van Mons. Nothing further is known of its origin.

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BERCKMANS

Prunus triflora