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 individual 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 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. Adan-son 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 et Hooker, Gray and his co-workers in the several revisions of his botany, and Engler et 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 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.
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 fewr, 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. Nearfy 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.
Of all the stone-fruits plums furnish the greatest diversity of kinds. Varieties to the number of two thousand, from fifteen species, are now 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 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 environmentfood, moisture and lightmany 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 of consideration though quite too much has been made of these characters, especially of pubescence, in determining species, for they are all extremely variable.
J. JJ. HORTULANA MINER! 2. Is. 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 coriaceous-ness, 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.
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.
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 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 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 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.
A. Flowers in clusters of i or 2. (Three in P. triflora.) Old World plums B. Leaves drooping.
C. Shoots and pedicels pubescent. D. Flowers mostly in twos.
E. Fruits large, more than 1 inch in diameter, variable in shape, often compressed; tree
large; stamens about 30.................... 1. P. domestica.
E.E. Fruit small, less than 1 inch in diameter, uniformly oval or ovoid; stamens about 25; tree small, compact................,,,.... 2. P. insititia.
D.D. Flowers mostly single.
E. Leaves small, less than 2 inches in length; sometimes a tree; very thorny..............3. P. spinosa.
E.E. Leaves large, more than z\ inches in length; a shrub; thorns few.................4- P- curdica.
C.C. Shoots glabrous or soon becoming so, pedicels glabrous.
D. Pedicels shorter than the calyx-cup; leaves glabrous or sparsely pubescent on the under side along the rib; flowers in pairs..............................5+ P. cocomilia.
D.D. Pedicels more than twice as long as the calyx-cup.
E. Flowers mostly single; leaves hairy along the midrib on the under side; petiole | as long as the leaf-blade; a tree................... 6. P. cerasifera.
E.E. Flowers in threes; leaves glabrous, petiole shining, leaf-margins finely and closely serrate, teeth glandular-pointed; stamens about 25 .... 7. P. monticola. E.E.E. Flowers in threes; leaves glabrous, often shining, leaf-margins finely and closely serrate, teeth glandular-pointed; stamens about 25... 8. P. triflora. B.B. Leaves upright, peach-like, glabrous, veins very conspicuous, under side barbate at axils of veins; separated from all other plums by the leaf-characters and by the large, flattened, brick-red fruits 9. P. simonii. A.A. Flowers in clusters of 3 or more, rarely 2. American plums. B. Plants trees. (P. angustifolia rarely a tree.) C. Leaves broad, mostly ovate or obovate.
D. Leaves long-ovate or long-obovate. E. Flowers white.
F. Leaf-serrations glandless, acute; petiole usually glandless; calyx-lobes entire, glabrous on the outer, pubescent on the inner surface; stamens about 30; stone turgid, large, pointed at the apex.....10. P. americana.
F.F. Leaf-serrations glandular, wavy-crenate; petioles glandular; calyx-lobes glandular-serrate, pubescent on the inner surface; stamens about 20; stone turgid, small, prolonged at the ends. .11. P. hortulana. E.E. Flowers fading to pink.
F. Leaf-serrations coarse, rounded, glandular only when young; petioles bi-glandular; calyx-lobes glandular-serrate, not pubescent on the inner surface; stamens about 30; fruit red; bloom light; stone flat.....................12. P. nigra.
F.F. Leaf-serrations fine, acute, glandular-pointed; petioles biglandular; calyx-lobes entire, pubescent on the outer, tomentose on the inner surface; fruits dark purple; bloom heavy; stone turgid, acute at the ends................... .13. P. alleghaniensis.
D.D. Leaves round-ovate, obtusely, sometimes doubly serrate; petioles glandless; calyx-lobes pubescent on both surfaces; fruit dark red or purplish; stone turgid, pointed at both ends.............................14. P. subcoretata,
C.C. Leaves narrow, lanceolate-ovate. D. Leaves flat.
E. Leaves glabrous; fruits globular, usually purple at maturity but sometimes red or orange-red; bloom thin; stone turgid, cherry-like.... .15. P. umbellata. E.E. Leaves pubescent.
F. Stone acute at both ends; fruit purple.16. P. mitis. F.F. Stone rounded at base; fruits variously colored.......................17. P. tarda.
D.D. Leaves more or less folded upward.
E. Fruits small, J inch in diameter, cherry-like; leaves lanceolate, upper surface glabrous, lustrous, lower surface pubescent in axils of veins, marginal teeth glandless; petioles bi-glandular; stone small, ovoid, turgid, cherry-like; rarely a tree; tender in New York......18. P. angustifolia.
E.E. Fruits large, an inch in diameter, plum-like; leaves lanceolate, peach-like, upper surface glabrous, lower surface pubescent along the midrib; petioles with from 1 to 6 glands; stone compressed and pointed at both ends; usually a tree; hardy in New York...........19. P. munsoniana
B.B. Plants shrubs.
C. Fruits dark purple.
D. Leaves ovate, acute, finely serrated; shoots becoming glabrous; stones pointed at both ends..............20. P. maritima.
D.D. Leaves oval-orbicular, crenate-serrate; shoots usually pubescent; stone pointed only at the base. .21. P. gravesii, C.C. Fruits red or orange, sometimes yellow but never deep purple.
D. Fruits large, 1 inch in diameter; leaves oblong-ovate, long-pointed, margin serrate with incurved sometimes glandular teeth, upper surface glabrous, lower surface pilose; petiole with 1 or 2 glands; stone oval, flattened..................................22, P. orthosepela.
D.D. Fruits small, i inch in diameter.
E. Leaves small, ovate-lanceolate or oval, margins finely and evenly serrate, upper surface glabrous, lower surface soft pubescent; petioles short and stout; fruits variable in color, mostly red; stone turgid, pointed at both ends......23. P. gracilis,
E.E. Leaves oblong-ovate, margins coarsely or doubly serrate, glabrous above and sparingly pubescent below; petiole glandular; fruits cherry-red................................24. P. rivularis.
1. PRUNUS DOMESTICA Linnaeus
1. Linnaeus Sp. PL 475. 1753. 2. Duhamel Traite des Arb. 2:93,
*768. 3. Seringe DC. Prodr. 2:533. l825- 4* Hooker Brit. Fl. 220. 1830.
5. London Arb. Fr. Brit. 1844. 6. De Canciolle Or. Cult. Pl. 212. 1885.
7. Schwarz Forst. Bot. 338. 1892. 8. Koch, W. Syn. Bent, und Schw. Fl.
1:727. 1892. 9. Dippel Handb. Laubh. 3:636. 1893. I0- Lucas Handb.
Obst. 429. 1893. 11. Waugh Bot. Gaz. 26:417-27. 1898. 12. Bailey Cyc.
Am. Hort. 1448. 1901. 13. Waugh Plum Cult. 14. 1901. 14. Schneider
Handb. Laubh. 1:630. 1906.
P. communis domestica. 15. Hudson Fl. Anglic. 212. 1778. 16. Bentham Handb. Brit. Fl. 1:236. 1865.
P. ceconomica (in part) and P. italica (in part). 17. Borkhausen Handb. Forstb. 2:1401, 1409. 1803. 18. Koch, K. Dend. 1:94, 96. 1869. I9; Koehne Deut. Dend. 316. 1893.
Tree reaching a height of 30 or 40 feet, vigorous, open-headed, round-topped; trunk attaining a foot or more in diameter; bark thick, ashy-gray with a tinge of red, nearly smooth or roughened with transverse lines; branches upright or spreading, straight, stout and rigid, usually spineless; branchlets usually pubescent, light red the first year, becoming much darker or drab; lenticels small, raised, conspicuous, orange.
Winter-buds large, conical, pointed, pubescent, free or appressed; leaves large, ovate or obovate, elliptical or oblong-elliptical, thick and firm in texture; upper surface dull green, rugose, glabrous or nearly so, the lower one paler with little or much tomentum, much reticulated; margins coarsely and irregularly crenate or serrate, often doubly so, teeth usually glandular; petioles a half-inch or more in length, stoutish, pubescent, tinged with red; glands usually two, often lacking, sometimes several, globose, greenish-yellow; stipules very small, less than a half-inch, lanceolate, narrow, serrate, early caducous.
Flowers appearing after or sometimes with the leaves, showy, an inch or more across, greenish-white to creamy-white; borne on lateral spurs or sometimes from lateral buds on one-year-old wood, 1 or 2 from a bud in a more or less fascicled umbel; pedicels a half-inch or more in length, stout, green; calyx-tube campanulate, glabrous or pubescent, green; calyx-lobes broadly oblong, obtuse, pubescent on both surfaces, glandular-serrate, usually reflexed; petals white or creamy in the bud, oval to obovate, crenate, notched or entire, claw short and broad; stamens about 30, equal to or shorter than the petals; anthers yellow, sometimes tinged with red; pistils about as long as the stamens, glabrous or pubescent.
Fruit of various shapes, mostly globular or sulcate, often necked, blue, red or yellow; stem a half-inch or more long, stout, pubescent; cavity shallow and narrow; apex variable, usually rounded; suture prominent or sometimes but a line or indistinct; skin variable; dots small, numerous, inconspicuous; flesh yellowish, firm, meaty, sweet or acid and of many flavors; stone free or clinging, large, oval, flattened, blunt, pointed or necked, slightly roughened or pitted; walls thick; one suture ridged, the other grooved.
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 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 ceconomica, 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 gave specific names to a number of plums which Schneider 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 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.
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.
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 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.
Pliny gives the first clear account of Domestica plums and speaks of them as if they had been but recently introduced. His account is as follows: " Next comes a vast number of varieties of the plum, the particolored, the black, the white, the barley plum, so-called because it is ripe at Barley harvest, and another of the same color as the last, but which ripens later, and is of a larger size, generally known as the 'Asinina,' from the little esteem in which it is held. There are the onychina, too, the cerina,more esteemed, and the purple plum; the Armenian, also an exotic from foreign parts, the only one among the plums that recommends itself by its smell. The plum tree grafted on the nut exhibits what we may call a piece of impudence quite its own, for it produces a fruit that has all the appearance of the parent stock, together with the juice of the adopted fruit; in consequence of its being thus compounded of both, it is known by the name of 'nuci-pruna.' Nut-prunes, as well as the peach, the wild plum and the cerina, are often put in casks and so kept till the crop comes of the following year. All the other varieties ripen with the greatest rapidity and pass off just as quickly. More recently, in Baetica, they have begun to introduce what they call ' malina,' or the fruit of the plum engrafted on the apple tree, and ' amygdalina,' the fruit of the plum engrafted on the almond tree, the kernel found in the stone of these last being that of the almond. Indeed, there is no specimen in which two fruits have been more ingeniously combined in one. Among the foreign trees we have already spoken of the Damascene plum, so-called from Damascus, in Syria, but introduced long since into Italy, though the stone of this plum is larger than usual, and the flesh small in quantity. This plum will never dry so far as to wrinkle; to effect that, it needs the sun of its own native country. The myxa, too, may be mentioned as being the fellow countryman of the Damascene; it has of late been introduced into Rome and has been grown engrafted upon the sorb."
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. 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, speaking of prunes in particular, gives the following account (translated) of their Asiatic origin:
"According to my investigation Turkestan and the southern Altai Mountains are the place of origin. When in the year 1844 I found myself in Baku on the west coast of the Caspian Sea, I had plenty of opportunity to draw accounts of the fruits of their native lands from the Turkestan and Bokharan merchants, and was astonished over the high cultivation of stone fruits in these placesat the same time I was able to taste dried the most choice because best flavored, the Ali-Bokhara, that is Bokhara prune. Some of these Bokharan prunes were transplanted a long time ago to Trans-Caucasia and were especially cultivated in the ancient city and residence of the Ruler of the modern Elizabethpol. Unfortunately the cultivation is less now than in earlier times. A further spread toward the west and toward Europe, I have not been able to follow. In Greece, the prunes are even to-day an unknown fruit."
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 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 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." * 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." 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.
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." 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 Quinceset, Cherries, Damsons, set the dames a work, marmalad and preserved Damsons
is to be met with in every house" (55)
In 1797 there is the following concise account of the plums
cultivated in New England:
"The better sorts which are cultivated are the horse plum, a very pleasant tasted fruit, of large size; the peach plum, red toward the sun, with an agreeable tartness; the pear plum, so-called from its shape, which is sweet, and of an excellent taste; the wheat plum, extremely sweet, oval, and furrowed in the middle, not large; the green-gage plum, which is generally preferred before all the rest."
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, writing in 1722 of Virginia, says: "Peaches, Nectarines and Apricocks, as well as plums and cherries, grow there upon standard trees," with the further statement that these fruits grew so exceedingly well that there was no need of grafting or inoculating them. Lawson, 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 Andrd 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. 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 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 founded by Dr. Andrew Turnbull at New Smyrna, Florida, in 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 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, "that his father, about the 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 " 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. (64) To this nursery, to William Prince and to William Robert Prince, (65) 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. 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 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 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 (68).
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 (69). 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. (70)
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 fruitgrowing 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.
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 Century, horticulture, in fact all agriculture, was greatly stimulated by the publication of agricultural books and magazines and the formation of agricultural and horticultural societies. 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 fruitgrowers. 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 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 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. The early history is not so well known.
Where the Reine Claude plums originated no one knows. Koch 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 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 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 knew the fruit, for he says:
"then are the wicker baskets eramm'd With Damask and Armenian and Wax plums."
And so, too, Pliny refers to them 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 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 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 enumerates it in his sixty sorts describing it as "a great, fine, green shining plum fit to preserve." Rea in 1676 also lists and describes it as does Ray, 1688.
It is doubtful if Parkinson, Ray and Rea had the true Reine Claude, however, for the Verdacchio, according to Gallesio, 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 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 gives the following account of its introduction into England:
"The Gage family, in the last century, procured from the monastery of the Chartreuse at Paris, a collection of fruit trees. When these trees arrived at the Mansion of Hengrave Hall, the tickets were safely affixed to all of them, excepting only to the Reine Claude, which had either not been put on, or had been rubbed off in the package. The gardener, therefore9 being ignorant of the name, called it, when it first bore fruit, the Green Gage"
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.
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. 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," but in such a way as to lead one to believe that neither it, nor any other prune, was then cultivated in America. (90) In 1831 William Robert Prince in his Pomological 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.
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 (91). 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.
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 (93). The name comes from an old time geographical division of Italy (94). 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, the}^ 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. (95) 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, 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 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 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 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.
The following sorts may be named as belonging here: Lombard, Bradshaw, Victoria, Pond, Duane, Autumn Compote, Belle, Middleburg and Field.
2. PRUNUS INSITITIA Linnaeus
1. Linnaeus Antoen. Acad. 4:273. 1755. 2. Seringe DC. Prodr. 2:532. 1825. 3. Hooker Brit. Fl. 220. 1830. 4. Loudon Arb. Fr. Brit. 2:687. 1844. 5. Koch, K. Dend. 1:95. 1869. 6. Ibid. Deut. Obst. 144. 1876. 7. De Candolle Or. Cult. Pl. 211. 1885. 8. Emerson Trees of Mass. Ed. 4:512. 1887. 9. Schwarz Forst. Bot. 339. 1892. 10. Koch, W. Syn. Deut. und Schw. Fl. 1:726. 1892. 11. Koehne Deut. Dend. 316. 1893. 12. Dippel Handb. Laubh. 3:639. 1893. 13. Lucas. Handb. Obst. 429. 1893. 14. Beck von Managetta Nied. Oester. 819. 1893.
P. communis (in part). 15. Hudson Fl. Anglic. 212. 1778. 16. Bentham Handb. Brit. Fl. 1:236. 1865.
P. domestica insititia. 17. Schneider Handb. Laubh. 1: 630. 1892. 18. Waugh Bot. Gaz. 27:478. 1899.
Tree dwarfish but thrifty, attaining a height of twenty to twenty-five feet ; trunk reaches eight inches in diameter and bears its head rather low, three to five feet from the ground; bark gray with a tinge of red, smooth, with transverse cracks; branches upright-spreading, rigid, compact, short-jointed, and more or less thorny; branchlets pubescent, slender, reddish-brown or drab.
Winter-buds small, conical, pointed or obtuse, free or appressed; leaves small, ovate or obovate; apex obtuse or abruptly pointed, base cuneate or narrowed and rounded, margins finely and closely, sometimes doubly serrate or crenate, usually glandular; texture thin and firm; upper surface slightly rugose, dark green, slightly hairy; lower surface paler and soft, pubescent; petioles one-half inch long, slender, pubescent, tinged with red; glands few or glandless.
Flowers expand with or after the leaves, one inch or less in size; borne variously but usually in lateral, umbel-like clusters, one, two or rarely three from a bud, on slender pedicels, which are pubescent and one-half inch in length; calyx-tube cam-panulate, glabrous or nearly so, green or tinged with red; calyx-lobes narrow, obtuse or acute, glandular-serrate, glabrous or pubescent, reflexed; petals white or creamy in the bud, broadly oval, entire or dentate, reflexed, claw short; stamens about twenty-five, as long as the petals; anthers yellow, often tinged with red; pistil glabrous and nearly as long as the stamens.
Fruit ripens from early to late; globular or oval, often necked, less than an inch in diameter, variously colored but usually bluish-black or amber-yellow, with a heavy bloom; skin thin, tough; stem slender, one-half inch long, more or less pubescent; cavity shallow, narrow; apex roundish or flattened; suture indistinct or a line; flesh firm, yellow, juicy, sweet or acid; stone clinging or free, somewhat turgid, ovoid, nearly smooth, ridged on one edge and grooved on the other.
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 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 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 Domes-ticas, almost wholly lacking this quality. These plums have been cultivated over two thousand years, yet there is seemingly little difference 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 subsylvesiris Boutigny and Prunus pomarium Boutigny belong to Prunus insititia and almost beyond question Prunus syriaca Koehne is the yellow-fruited Mirabelle of this species. Prunus insititia glaberrima Wirtg, 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, 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. 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:
"then are the wicker baskets cramm'd With Damask and Armenian and Wax plums."
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 has illustrated and described stones of a plum found 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 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 Domes-ticas, and
others who combine these two with the Spinosa plums in one species,
Prunus communis (107)
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 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, 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 Pomo-logical 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 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 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 how 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 nursery-men's 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 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 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. St. Julien plums are seemingly nowhere grown at present for their fruits.
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.
1. Linnaeus Sp. PL 475. 1753. 2. Hudson Fl. Anglic. 186. 1778. 3. Ehrhart Beitr. Nat. 4:16. 1789. 4. Pursh Fl. Am. Sept. 1:333. X8i4- 5. Hooker Fl. Bor. Am. 1:167. 1833. 6. Tor-rey and Gray FL N. Am. 1:408. 1840. 7. Koch, K. Bend. 1:98. 1869. 8. Ibid. Deut. Obst. 143. 1876. 9. DeCandolle Or. Cult. PL 212. 1885. 10. Schwarz Forst Bot. 339. 1892. n. Koch, W. Syn. Deut. und Schw. FL 1:726. 1892. 12. Dippel Handb. Laubh. 3:637. 1893. 13. Koehne Deut. Dend. 316. 1893. 14. Beck von Managetta Nied. Oester. 818. 1893. 15. Bailey Cyc. Ant. Hort. 1447 fig. 1901. 16. Schneider Handb. Laubh. 1:628. 1906.
Plant low, spreading, much-branched, thorny, shrubby, seldom attaining the dimensions of a small tree; branchlets distinctly pubescent; leaves small, ovate or oblong-ovate, sometimes obovate, numerous, nearly glabrous at maturity, obtuse at the apex, cuneate or rounded at the base, margins closely and finely serrate.
Flowers white, one-third or one-half inch in diameter, expanding before the leaves; borne singly, in pairs or sometimes in threes, in lateral clusters.
Fruit globose, usually less than one-half inch in diameter, dark blue, almost black, with a heavy bloom; flesh juicy, firm, with an acid, austere taste, scarcely edible for a dessert fruit but making a very good conserve; stone turgid or but little flattened, acute on one edge.
European botanists commonly break the species into a number of sub-species, as: Prunus spinosa typica Schneider, flower-pedicels and calyx-cup glabrous; Prunus spinosa praecox Wim. and Grab., pedicels short, blossoms appearing before the leaves; Prunus spinosa sessiliflora Beck, with sessile flowers, possibly the same as the next preceding form; Prunus spinosa coatanea Wim. and Grab., blossoming with the leaves and with long pedicels; and Prunus spinosa dasyphylla Schur., 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 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 Prunus fruticans Weihe and Prunus spinosa macrocarpa Wallroth 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.
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.
1. Fenzl and Fritsch Sitzb. Akad. Wien. Bd. CI. 1:627. 1892. 2. Schneider Handb. Laubh. 1:628. 1906.
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. 1. Tenore Fl. Neap. Prodr. Suppl. 2:68. 1811. 2. Schneider Handb. Laubh. 1:628. 1906.
Tree shrub-like, top thick, broadly ovate; branches drooping, shoots short; branch-lets glabrous, young wood olive or reddish-brown. Buds small, roundish-ovate; leaves roundish-obovate, sharply and distinctly serrated, glabrous or upon the ribs on the under side sparsely pubescent. Flowers usually in pairs, opening before or with the leaves, greenish-white, pedicels about the length of the calyx-cups. Fruit yellow, agreeable.
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. 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 which differs only in minor respects from the species, chiefly in having violet-red fruit though Boissier 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 (123)
1. Ehrhart Beitr. Nat. 4:17. 1789. 2. Hooker Brit. Fl. 220. 1830. 3. Koch, %L. Dend. 1:97. 1869. 4. Koch, W. Syn. Deut. und Schw. Fl. 1:727. 1892. 5. Bailey Cornell Sta. Bid. 38: 66. 1892. 6. Schneider Handb. Laubh[ 1:632. 1892. 7. Schwarz Forst. Bot. 339. 1892. 8. Dippel Handb. Laubh. 1:633. 1893.
P. domestica myrobalan. 9. Linnaeus Sp. PL 475. 1753. 10. Seringe DC. Prodr. 2:538. 1825.
P. myrobalan. 11. Loisleur Nouv. Duham. 5:184. 1812. 12. Koehne Deut, Dend. 316. 1893.
Tree small or a tree-like shrub, seldom exceeding twenty-five feet in height; branches upright, slender, twiggy, unarmed or sometimes thorny; branchlets soon glabrous, becoming yellow or chestnut-brown; lenticels few, small, orange in color, raised.
Winter-buds small, obtuse, short-pointed, pale reddish-brown; leaves small, short-ovate, apex acute, base cuneate or rounded, thin, membranaceous, texture firm, light green, nearly glabrous on both surfaces at maturity, though hairy along the rib on the lower surface, margins finely and closely serrate; petiole one-half or three-quarters of an inch long, slender, usually glabrous, glandless.
Flowers large, three-quarters of an inch in diameter, expanding very early or mostly with the leaves; calyx-lobes lanceolate, glandular, reflexed; petals white, sometimes with a blush, ovate-oblong or orbicular, the base contracted into a claw; borne singly, sometimes in pairs, in cymes on long, slender, glabrous peduncles.
Fruit small, one-half inch or a little more in diameter, globular or depressed-globular, cherry-like, red or yellow; skin thin and tender; flesh soft, juicy, sweet and rather pleasantly flavored; stone oval, short-pointed at both ends, somewhat turgid, ridged on one suture and grooved on the other.
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 Tabernae-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 is now considered 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, 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.
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 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 reports that seeds from the purple-leaved plum have produced plants which agree in all essential particulars with the species; while Kerr 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 calls Prunus dasycarpa Ehrhart, the Prunus armeniaca dasycarpa of Borkhausen, a cross between Prunus cerasifera and Prunus armeniaca, one of the apricots.
7. PRUNUS MONTICOLA K. Koch
I, Koch, K. Ind. Setn. Hort. Berol. App. 1854. 2. Schneider Handb. Laubh. 1:632. 1906.
Plant shrub-like, slender, upright, scarcely thorny, new wood more or less olive-brown. Buds short, ovate; leaves roundish or cuneiform, base oblong-ovate, point drawn out, main nerves over six on both sides, the serrations coarse and uniform in size, always glabrous. Flowers mostly in twos; borne on long, slender peduncles; calyx usually glabrous; petals white, odor slight; stamens thirty or more. Fruit small, roundish-oblong, red; stone ovoid, pointed at one end, somewhat turgid.
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 [later renamed Prunus salicina -ASC]
1. Roxburgh Hort. Bengal 38. 1814. 2. Ibid. Fl. Indica 2:501. 1824. 3. Schneider Handb. Laubh. 1:627. 1892. 4. Bailey Cornell Sta. Bul. 62. 1894. 5. Waugh Plum Cult. 42. 1901. P. domestica. 6. Maximowicz Mel. Biol. 11:678. 1883. P. kalian Tamar1. 7. Bailey An. Hort. 30. 1889.
P. communis. 8. Forbes and Hemsley Jour. Linn. Soc. 23:219. 1886-88. P. japonica of horticulturists (not P. japonica of Thunberg).
Tree twenty to thirty feet in height, vigorous; trunk six to twelve inches in diameter, straight; bark thick, rough, numerous corky elevations especially on the branches, reddish or cinnamon-brown, peach-like; branches long, upright-spreading, much forked, brash and often splitting at the forks; branchlets thick, straight, glaucous and glabrous, at first light red, growing darker the second year; lenticels few or many, usually small but conspicuous, light in color.
Winter-buds small and obtuse, free or appressed; leaves borne abundantly, small or of but medium size, oblong-obovate, point acuminate or abrupt, prominent, base rounded, firm, thin, membranaceous, margins finely and closely serrated, sometimes in two series, teeth usually glandular; upper surface bright green, glabrous, lower surface dull, whitish, glabrous or slightly pubescent on the veins; veins pronounced; petioles one-half inch in length, stoutish, tinged with red; glands few or several, usually globose, greenish; stipules lanceolate, very narrow, one-half inch long, caducous.
Flowers expanding early, before, with or sometimes after the leaves, first of the plum blossoms to appear, very abundant, three-quarters of an inch in diameter; usually three springing from each flower-bud, often in dense clusters on lateral spurs and lateral buds on one-year-old wood; calyx-tube green, glabrous, campanulate or obconic; calyx-lobes acute to obtuse glandular-serrate, erect, glabrous or pubescent; petals white, oval, entire or crenate, with a short claw or tip; stamens about twenty-five, shorter than the petals; anthers yellow, sometimes tinged with red; pistils glabrous, longer than the stamens; pedicels one-half inch long, slender.
Fruit varying greatly in season,kfrom very early to late; large, from one to two inches in diameter, globular, heart-shaped or often somewhat conical; cavity deep; apex conspicuously pointed; suture usually prominent; color varies greatly but usually a bright red or yellow, never blue or purple, lustrous, with little or no bloom; dots small, numerous, usually conspicuous; skin thin, tough, astringent; stem one-half inch in length; flesh red or more often yellow, firm, fibrous, juicy; quality variable, of distinct flavor, usually good; stone clinging tenaciously or nearly free, small, rough or lightly pitted, oval to ovate, one edge grooved, the other ridged.
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 simoni (132). 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, Prunus thibetica Franchet and Prunus bokhariensis Royle, 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, 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. 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 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, that Prunus triflora does not grow wild in Japan but was introduced there from China from two to four hundred years ago. Bretschneider 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 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 that the shrub had been " received from China into our gardens in Bengal" Forbes and Hemsley 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, Sie-bold 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, 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, 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 et 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 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 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, Bailey and Waugh, 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 somewThat 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.
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 * " 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 Carriere
1. Carriere Rev. Hort. in. 1872.
For [additional] references and synonymy see the Simon plum.
Tree small, of medium vigor, upright, dense, hardy except in exposed locations, unproductive; branches stocky, long, rough, thickly strewn with small lenticels; branchlets slender, long, with internodes of medium length, reddish, glabrous; leaf-buds intermediate in size, short, obtuse, free.
Leaves folded upward, oblong-lanceolate to obovate, peach-like, narrow, long, of medium thickness; upper surface dark green, smooth, shining, lower surface pale green, not pubescent, with prominent midrib; margin slightly crenate; petiole short, thick, faintly tinged red, often with four large globose glands on the stalk.
Flower-buds numerous on one-year wood although found on spurs on the older wood; flowers appearing very early, semi-hardy, small, pinkish-white; borne singly or in pairs, often defective in pollen.
Fruit maturing early; one and three-quarters by two and one-quarter inches in size, strongly oblate, compressed; cavity deep, wide, flaring, regular, often slightly russeted; suture variable in depth, frequently swollen near the apex which is flattened or strongly depressed; dark red or purplish-red, overspread with waxy bloom; dots numerous, small, dark colored, with russet center, inconspicuous; stem thick, characteristically short being often one-quarter inch long; skin of medium thickness, tough, bitter, adhering to the pulp; flesh rich yellow, medium juicy, tough, firm, very mild sub-acid with a peculiar aromatic flavor; of fair quality; stone clinging, about seven-eighths inch in diameter, roundish, flattened to rather turgid, truncate at the base, tapering abruptly to a short point at the apex, with characteristic rough surfaces; ventral suture narrow, acute or with distinct wing; dorsal suture very blunt or acute, not grooved.
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 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
1. Marshall Arb. Am. in. 1785. 2. Eaton and Wright N. Am. BoL 377. 1840. 3. Torrey and Gray Fl. N. Am. 1:407. 1840 (in part). 4. Torrey Fl. N. Y. 1:194. 1843 (in part). 5. Emerson Trees of Mass. 449. 1846. 6. Nuttal Silva 2:19. 1846. 7. Darlington Fl. Cest. Ed. 3:72. 1853. 8. Torrey Pac. R. Rpt. 4:82. 1854. 9. Curtis Rpt. Geol. Surv. N. C. 56. i860. 10. Ridg-way Proc. U. S. Nat. Mus. 65. 1882. 11. Sargent 10th Cen. U. S. 9:65. 1883 (in part). 12. Watson and Coulter Gray'sMan.Ed.6-.151. 1889 (in part). 13. Coulter Cont. U.S.Nat. Herb. 2:102. 1891. 14. SargentSilvaN. Am. 4:19, PL 150. 1892, 15. Rydberg Cont. U. S.Nat.Herb. 3:156. 1895. 16. Ibid. 3:494. 1896. 17. Waugh Vt. Sta. Bul. 53:59. 1896. 18. Ibid. Vt. Sta. An. Rpt. 10:100. 1896-7. 19. Chapman FL Sou. U. S. 130. 1897. 20- Bailey Ev. Nat. Fr. 182, fig. 1898. 21. Waugh Vt. Sta. An. Rpt. 12:231. 1899. 22. Mohr Cont. U. S.Nat. Herb. 6:551. 1901. 23. Bailey Cyc. Am. Hort. 1448 fig. 1901. 24. Rydberg Fl. of Colo. 193. 1906.
Tree attaining a height of thirty feet, slow but strong in growth, often shrubby; trunk thick, sometimes a foot in diameter, short, bearing the head at three to five feet; bark one-half inch thick, dark grayish-brown, outer surface rough, shaggy with large scales, with age becoming smoother, giving a characteristic aspect; branches spreading, crooked, long, rigid, but often pendulous at the extremities, more or less thorny, with lateral, spinescent branchlets; branchlets light green, usually glabrous, sometimes much or little tomentose, at first becoming brownish and later tinged with red; lenticels numerous, large and distinct.
Winter-buds medium in size, short, acute, appressed, reddish-brown; leaves large, obovate, oblong-obovate, or oval, acuminate at the apex and usually rounded at the base, thin and firm in texture, becoming somewhat coriaceous; margins sharply serrate, almost incised, often doubly serrate, the coarse and double serrations characteristic; teeth not glandular; upper surface more or less roughened, light green, the lower one glabrous or slightly hairy, sometimes pubescent, coarsely veined, the midrib grooved on the upper side; petioles slender, two-thirds inch in length, usually glandless; stipules long, sometimes three-lobed, falling early.
Flowers expanding after the leaves, large, an inch in diameter, borne in lateral umbels, two to five-flowered, mostly on one-year-old wood; pedicels one-half inch long, slender, usually glabrous; calyx-tube obconic, entire, glandular, reddish on the outer, green on the inner surface, glabrous; calyx-lobes acuminate, glabrous on the outer and pubescent on the inner surface, reflexed; petals white, sometimes with bright red at the base, rounded and often lanciniate at the apex, contracted into a long, narrow claw at the base; stamens about thirty in number, as long as the petals; anthers small, yellow; pistils glabrous, slender, as long as the stamens; stigma thick and truncate; anthers and pistils often defective; when in full flower emitting a disagreeable odor.
Fruit very variable in ripening period; globose, sub-globose, conical, oval, or sometimes oblique-truncate, usually more than an inch in diameter, red or rarely yellowish, mostly dull, with or without bloom; dots pale, numerous, more or less conspicuous; cavity shallow or almost lacking; suture a line; skin thick, tough, usually astringent; flesh golden-yellow, juicy, meaty, fibrous, sweetish, acid and poor but often good to very good; stone clinging or free, turgid or flattened, the apex pointed, ridged on the ventral and slightly grooved on the dorsal suture, surfaces smooth. .
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, 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. It 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 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.
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.
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 yellowin 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 t 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 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, 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 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 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 Torrey and Gray
1. Torrey and Gray Fl. N. Am. 1:407. 1840. 2. Sargent 1.0th Cen. U. S. 9:65. 1883. 3. Coulter Cont. U. S. Nat. Herb. 2:102. 1891. 4. Sargent Sil. N. Am. 4:19. 1892. 5. Waugh Bot. Gaz. 26:50. 1898.
P. americana lanata. 6. Sudworth Nom. Arb. Fl. U. S. 237. 1897.
P. lanata. 7. Mackenzie and Bush Trans. Acad. Sc1. St. Louis 12:83. 1902.
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 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
1. Bailey Gar. and For. 5:90. 1892. 2. Sargent Sil. N. Am. 4:23, Pl. 151. 1892. 3. Waugh Vt. Sta. An. Rpt. 10:99-105. 1897. 4. Mohr Torrey Bot. Club Bul. 26:118. 1899. 5; Bailey Cyc. Am. Hort. 1450, fig. 1901. 6. Mohr Cont. U. S. Nat. Herb. 6:551. 1901.
P. americanay var. ? 7. Patterson List Pl. Oquawka 5. 1874.
Tree attaining a height of thirty feet or more, vigorous in growth; trunk sometimes a foot in diameter; trunk and branches rough and shaggy becoming furrowed in age; bark gray-brown, thick and containing deposits of red cork cells which show as bright red blotches or as thick layers when the bark is sectioned, these deposits, especially in quantity, characterizing the species; branches very spreading and open, twiggy, slender, thorny; branchlets light green at first, becoming reddish-brown, glabrous and glossy; lenticels few, large, very coarse, raised, characteristic of the species.
Winter-buds plump, very small, obtuse, appressed; leaves one and three-quarters inches wide to five inches in length, long-oval with a tapering, pointed, acuminate apex, peach-like, base abrupt, texture thin, becoming leathery, margins serrate, almost crenate, sometimes in a double series, glandular; upper surface smooth, glossy, glabrous; lower surface light green, almost glabrous except on ribs and veins which are very pubescent, with characteristic orange color, midrib grooved above, rounded below, very prominent; petioles slender, an inch in length, pubescent on the upper side, tinged with red; glands two to eight, small, globose, mostly on the petioles.
Flowers expanding after the leaves, blooming later than any other cultivated plum, three-quarters inch across; odor disagreeable; clusters borne from lateral buds on one-year-old wood only, characterizing the species, the fruit-spurs making a very long growth, more like branches than the spurs of other species, two to six flowers from a bud; pedicels three-quarters inch long, very slender, glabrous; calyx-tube narrow, campanulate, glabrous, green; calyx-lobes narrow, acute, glandular-serrate, glands red, slightly pubescent on the inner side, erect; petals ovate, slightly crenate, dentate at the apex, tapering into long narrow claws; stamens about twenty in number, yellow; pistils glabrous, equal to or shorter than the stamens.
Fruit very late in ripening; globose, oval, an inch in diameter; color varying from shades of red to shades of yellow; bloom inconspicuous or lacking; dots numerous, small, conspicuous; suture very shallow or only a line; skin thick, tough, astringent; flesh golden-yellow, juicy, coarse, fibrous, firm, flavor mildly sweet, astringent at the pit, strongly aromatic; quality fair; stone clinging to the flesh, turgid, long-oval, small, prolonged at the ends, the surfaces rough and reticulated.
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 [likely the same as Golden Beauty -ASC], probably Wild Goose and others." Unfortunately Bailey later added 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 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 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 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 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 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
1. Bailey Cornell Sta. Bul. 38:23, 1892. 2. Waugh Vt. Sta. An. Rpt. 10:103. 1897. 3. Britton and Brown 2:247. 1897.
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 subspecies 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.
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
1. Aiton Hort. Kew. 2:165. 1789. 2. Sims Bot. Mag. 1117. 1808.
Fl. Am. Sept. 1:331. 1814. 4. Torrey Fl. U. S, 1:469. 1824. 5. Sargent
Silva N. Am. 4:15, Pl. 149. 1892. 6. Small Torrey Bot. Club Bul.
Cerasus nigra. 7. Loiseleur Nouveau Duhamel 5:32. 1812.
P. americana (in part), 8. Torrey and Gray FL N. Am. 1:407. 1840. 9. Torrey Fl. N. Y. 1:194. 1843. I0; Emerson Trees of Mass. Ed. 2, 2:511. 1846. 11. Nuttall Silva 2:19. 1852. 12. Sargent 10th Cen. U. S. 9:65. 1883. 13. Watson and Coulter Gray's Man. Ed. 6:151. 1889. 14. Gray For. Trees N. A. 46, PL 1891.
P. americana nigra. 15. Waugh Vt. Sta. Bul. 53:60, fig. 1896. 16. Ibid. Vt. Sta. An. Rpt. 10:102. 1897. 17. Bailey Cyc. Am. Hort. 1449. 1901.
P. mollis. 18. Torrey Fl. U. S. 1:470. 1824.
Tree small, seldom exceeding twenty feet in height; trunk attaining six or eight inches in diameter, bearing the head at three to five feet from the ground; bark thin, one-quarter inch thick, from dark red to a light gray-brown, rough, but not shaggy, surface covered with thick scales; branches upright, stout, rigid, forming a compact rather narrow head, armed with stout, spiny spurs; branchlets more or less zigzag, glabrous or tomentose, green, later becoming reddish-brown; lenticels few or many, pale, slightly raised.
Winter-buds of medium size, conical or long-acuminate, reddish-brown; leaves large, broad-oval, ovate or obovate, with a long acuminate apex and cuneate or sub-cordate base; margins doubly crenate-serrate with teeth tipped with glands which disappear as the leaves mature; thin and firm in texture; upper surface light green, glabrous, the under surface paler, pubescent when young and pubescent at maturity on some soils; midribs coarse but veins rather slender; petioles two-thirds inch long, rather stout, with two, sometimes but one, large, dark red glands near the blade, pubescent and tinged with red; stipules lanceolate, sometimes lobed, one-half inch in length.
Flowers expanding early, before or with the leaves, large, sometimes one and one-half inches across; borne in three or four-flowered lateral umbels on slender, glabrous, red pedicels one-half inch or more in length; calyx-tube obconic, outer surface red, inner surface pink; calyx-lobes glabrous on both surfaces or with a few, straight, scattered hairs on the inner surface, pinkish, acute, glandular; petals pink, turning a darker pink in fading, rather broadly ovate, apex rounded, base a short claw, margins erose; stamens with yellow anthers; filaments one-half inch long; pistils glabrous, shorter than the stamens.
Fruit ripening comparatively early; globose or oval, usually somewhat oblong, an inch or more through the long diameter, red, orange or yellowish in color, with little or no bloom; skin thick, tough and astringent; flesh yellow, firm, meaty, often acid or astringent; stone usually clinging, large, oval, compressed, thick-walled, with a sharp ridge on the ventral and a slight groove on the dorsal suture.
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. 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 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 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 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 bi-glandular, 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.
1. Porter Bot. Gaz. 2:85. 1877. 2. Ibid. Gar. and For. 3:428, fig. 53. 1890. 3. Sargent Sit. N. Am. 4:27, Pl. 153. 1892. 4. Bailey Ev. Nat. Fr. 225, 1898.
Tree low, slender, straggling, fifteen to eighteen feet in height, or a low shrub; trunk-diameter from five to eight inches; bark dark brown, surface fissured and scaly; branches numerous, upright, rigid, seldom spiny; branchlets pubescent, becoming glabrous and red, turning to dark brown; lenticels many, small, white.
Leaves ovate-oblong or lanceolate, sometimes obovate, apex acute or acuminate, base rounded, margin sharply serrate, teeth fine and tipped with glands, in texture thick and firm; upper surface dark green and glabrous; lower surface light green, glabrous except on the veins and midrib; petioles short, slender, pubescent; glands two, large, at the base of the blade.
Flowers white, fading to pink, one-half inch across, appearing with the leaves; borne in two to five-flowered umbels; pedicels slender, finely tomentose, from one-fourth to one-half inch in length; calyx-tube narrowly obconic; calyx-lobes entire, pubescent on the outer, tomentose on the inner surface; petals rounded but narrowing into claws at the base; filaments and ovary glabrous; anthers often reddish; style slender with a funnel-shaped apex.
Fruit matures in summer or early autumn; from one-quarter to three-quarters inch in diameter, sub-globose or ovoid, dark blue or purple with heavy bloom; skin thick and tough; flesh yellow, juicy, acid and somewhat astringent; stone clinging to the flesh, turgid, acute at the ends, thin-walled, ridged on the ventral and grooved on the dorsal suture.
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, 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 (157). 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 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
1. Bentham Pl. Hartweg. 308. 1848. 2. Torrey Pac. R. Rpt. 4:82. 1854. 3. Brewer and Watson Bot. Calif. 1:167. 1880 (m part). 4. Lemmon Pittonia 2:68. 1890. 5. Greene Fl. Francis 1:49. 1891. 6. Bailey Cornell Sta. Bul. 38:76. 1892. 7. Sargent Sil. N. Am. 4:31, 32, Pl. 154. 1892.
Tree small, rarely attaining a height of twenty-five feet, sometimes a shrub ten or twelve feet high and often a bush but three or four feet in height; trunk medium in length with a diameter of 8 to 12 inches; bark gray-brown and deeply fissured; branches stout and spreading; branchlets glabrous or pubescent, bright red becoming darker red and finally a dark-brown or gray; lenticels minute, whitish.
Leaves round-ovate, sub-cordate or truncate, or sometimes cuneate at the base; margins either sharply or obtusely serrate, sometimes doubly serrate; young leaves pubescent but at maturity nearly glabrous, somewhat coriaceous, dark green on the upper and pale green on the lower surface, with very conspicuous midribs and veins; stipules acute-lanceolate, caducous.
Flowers white, fading to rose, about an inch across; appearing before the leaves; usually borne in threes, often in pairs on short pubescent pedicels; calyx campanulate, with lobes pubescent on the outer and hairy on the inner surface; petals twice the length of the sepals, obovate, and contracted into short claws; filaments and ovary glabrous; style slender and funnel-shaped at the apex.
Fruit ripens in late summer or early autumn; roundish or oblong, about one inch in length, borne on a short, stout stem, dark red or purplish; flesh subacid, well-flavored, clinging to the flattish or turgid stone which varies greatly in size, pointed at both ends, crested on the ventral edge and grooved on the other.
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 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 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 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 (160). 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:
"In 1856 there was, on the Middle Yuba River, not far from Forest City, in Sierra County, a wayside establishment known as 'Plum Valley Ranch' so-called from the great quantity of wild plums growing on and about the place. The plum by cultivation gave a more vigorous growth and larger fruit. Transplanted from the mountains into the valley they are found to ripen earlier. Transplanted from the mountains to a farm near the coast, in Del Norte County, they did not thrive. One variety, moved from the hills near Petaluma in 1858, was grown as an orchard tree for fifteen years, and improved both in growth and quality of fruit by cultivation. * * * * Recently excellent results have been reported from the domestication of the native plum in Nevada County, and fruit shown at the State Fair of 1888 gave assurance that by cultivation and by selecting seedlings valuable varieties can be obtained. It is stated that in Sierra County the wild plum is the only plum which finds a market at good prices, and that cultivated gages, blue and egg plums scarcely pay for gathering. The wild plum makes delicious preserves."
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:
"The Prunus subcordata, as it grows wild, bears very heavily even on bushes two and three feet in height, bending the bushes flat on the ground when the fruit is ripe. This is a very beautiful sight. The wild ones, although almost invariably bright red and spherical, are sometimes, though rarely found, yellow. When the seed of the yellow fruit is planted a certain portion of red ones are produced, but all, practically, of the same size and quality as the original. The trees of Subcordata in the wild state are greatly variable in growth, generally much more so than in the fruit. The fruit, however, varies much in quality, but it is promiscuously gathered by those living in the vicinity of the plum grounds and considered most excellent for cooking. I commenced working on this species about twenty-two years ago and have not carried it on as extensively as with the Mari-tima, as I found it subject to plum-pockets, but by very careful selection I have produced most magnificent plums, oval in form or round, sweet as honey or sweet as the French Prune, greatly enlarged in size, tree improved in growth and enormously productive, the different varieties ripening through a long season. Most of these are light and dark red. Some of them, when cooked, are far superior to cranberries, having the exact delicious flavor so much liked in this fruit, and the same color.
" From the crosses of Subcordata with the Americana, Nigra, Triflora and other species, some of the most beautiful and highest flavored fruits which I have even seen have been produced. These vary in color from almost pure white to light yellow, transparent flesh color, pink, light crimson, scarlet, dark crimson and purple; in form round, egg-shaped or elongated-oval; trees both upright and weeping, enormously productive, and in one or two cases the fruit, by hundreds of experts, has been pronounced the best plum in flavor of any in existence. Most of these selections are extremely productive."
Wickson 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 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
1. Lemmon Pittonia 2:67. 1890. 2. Wickson Calif. Fr. Ed. 2:51. 1891. 3. Greene Fl. Francis 1:50. 1891. 4. Bailey Cyc. Am. Hort. 1448. 1901.
Prunus subcordata kelloggii, named in honor of Dr. Albert Kellogg, an early explorer and settler in California, is distinguished from the species in being a somewhat taller and more slender plant. 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 Shastay 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.
IS. PRUNUS UMBELLATA Elliott
1. Elliott Sk. Bot. S. C. andGa. 1:541. 1S21. 2. Sargent 10th Cen. U. S. 9:67. 1883. 3. Ibid. Sil. N. Am. 4:33, Pl. 155. 1892. 4. Waugh Plum Cult. 91. 1901. 5. Mohr Cont. U. S. Nat. Herb. 6:551. 1901.
Cerasus umbellata. 6. Torrey and Gray Fl. N. Am. 1:409. 1840.
Tree low, sometimes a shrub, seldom over twenty feet in height; trunk short, usually crooked, attaining a thickness of ten inches; bark dark brown and scaly; branches spreading, slender, twiggy but spineless; branchlets at first pubescent but becoming glabrous, bright red turning dark brown the second year; lenticels few, oblong, yellowish.
Leaves oblong-ovate, or oblong-obovate to oblong, thin and membranaceous, acute at the apex but usually obtuse or cordate at the base; margins closely and evenly serrate with glandular teeth, upper surface dark green and glabrous, lower surface pale green and more or less pubescent; petioles stout, glabrous or sometimes pubescent; glands usually two, sometimes wanting, large, dark, at the base of the leaf; stipules lanceolate, small, caducous.
Flowers medium in size, appearing before and with the leaves; usually borne in four-flowered umbels; calyx-tube obconic, its lobes entire, outer surface glabrous or pubescent, the inner densely tomentose; petals white, orbicular, clawed.
Fruit matures in late summer; one-half inch in diameter, nearly round, without cavity or suture, borne on a slender pedicel three-quarters inch long, orange-red or bright red to purple or nearly black, covered with a thin bloom; skin thick and tough; flesh coarse, thick, acid or astringent, scarcely edible; stone nearly free, flattened, acute at both ends, rugose, thin-walled.
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, 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
1. Sargent Sil. N. Am. 13:21. 1902.
Prunus injucunda. 2. Small Torrey. Bot. Club Bul. 25:149. 1898. 3. Mohr Ibid. 26:118. 1899. 4. Ibid. Cont. U. S. Nat. Herb. 6:552. 1901. 5. Bailey Cyc. Am. Hort. 1449. 1901.
Tree low, seldom twenty feet in height, often a straggling shrub; trunk short, crooked, attaining a diameter of eight inches; bark dark brown, nearly black; branches slender, rigid, twiggy and somewhat spiny; branchlets velvety becoming purplish and finally a dull gray; lenticels few, yellowish.
Leaves oblong-ovate to obovate, taper-pointed at the apex and obtuse or rounded at the base, margins closely and finely toothed, thin in texture; upper surface yellowish-green, wrinkled and more or less pubescent, lower surface densely pubescent and with a prominent yellowish midrib and rather prominent lateral veins; petioles stout, one-half inch in length, very pubescent; stipules lanceolate, small, caducous.
Flowers medium in size or small, usually appearing before the leaves; in four or five-flowered sub-sessile umbels; pedicels slender, three-quarters inch in length, very pubescent; calyx-tube obconic, tomentose, with erect, entire, sharply pointed, ciliate, tomentose lobes; petals white, orbicular, clawed; filaments and base of pistil tomentose. Fruit maturing in late summer, three-quarters inch long, oblong, with but a trace of cavity and suture, dark purple with light bloom; flesh thin, sour and very astringent; skin thick, tough; scarcely edible; stone ovoid, long, flat, roughish, pointed at both ends with a groove on one edge and a grooved ridge on the other.
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 1. Beadle Bilt. Bot. Stud. 1:162. 1902. 2. Britton and Brown N. Am. Trees 489. 1908.
Tree small, maximum height twenty-five feet; bark dark brown or reddish-gray; branches spreading or ascending, usually unarmed; branchlets glabrous, glaucous; leaves thin, elliptic, oblong-lanceolate, sometimes ovate or obovate, apex acute or acuminate, base narrow or rounded, margin sharply serrate; petioles less than one-half inch, densely pubescent, with two glands at or on the base of the leaf; upper surface bright green, finely pubescent, lower surface paler, also pubescent and with a prominent midrib and veins.
Flowers of medium size, appearing before the leaves; borne in sub-sessile, two to six-flowered umbels; calyx-tube obconic, smooth, its lobes triangular, pubescent on the outer and velvety on the inner surface; petals white, obovate, clawed; pedicels slender, smooth, three-quarters inch long.
Fruit ripening in mid-summer; over one-half inch in length, oblong, dark purple with a heavy bloom; stone ovoid or oval, flattened, nearly one-half inch long, pointed at both ends especially at the apex, and crested on one edge.
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 umbellatay 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 1. Sargent Bot. Gaz. 33:108. 1902. 2. Ibid. Sil. N. Am. 13:23, PL 632. 1902.
Tree from twenty to twenty-five feet in height; trunk tall, eighteen or twenty inches in diameter; bark light brown, reddish, thick, with flat ridges and plate-like scales; branches spreading, forming an open symmetrical head; branchlets slender, at first light green and tomentose becoming glabrous, light brownish and lustrous, and the second year much darker; lenticels small, dark, scattered.
Leaves oblong to obovate, apex acute and sharp-pointed, base rounded or cuneate, margin finely serrate with incurved, glandular teeth, in texture thick and firm; upper surface glabrous, dark yellow-green, lower surface pubescent, pale green; petioles stout, tomentose or pubescent, short, eglandular or with two stalked, dark glands at the apex; stipules acicular, often bright red, small.
Flowers three-quarters inch across, appearing before and with the leaves; borne in two or three-flowered umbels, on slender, glabrous pedicels; calyx-tube narrowly obconic, hairy above, the lobes acute, entire, villose on the outer, tomentose on the inner surface; petals oblong-obovate with a short claw at the base; filaments and pistils glabrous.
Fruit maturing very late; short-oblong to sub-globose, one-third to one-half inch in length, red, yellow, purple, black or blue; skin tough and thick; flesh thick and acid; stone adhering to the flesh, ovoid, more or less compressed, very rugose, ridged on the ventral and grooved on the dorsal suture, acute at the apex, rounded at the base.
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 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
I. Marshall Arb. Am. 111. 1785. 2. Torrey and Gray Fl. N. Am. 1:407. 1840. 3. Loudon Arb. Fr. Brit. 2:705. 1844. 4. Sargent 10th Cen. U. S. 9:66. 1883. 5. Watson and Coulter Gray's Man. Ed. 6:152. 1889 (in part). 6. Gray For. Trees N. A. 47, PL 1891. 7. Sargent Sil. N. Am. 4:25, Pl. 152. 1892. 8. Mohr Cont. U. S. Nat. Herb. 6:551. 1901.
P. chicasa. 9. Michaux Fl. Bor. Am. 1:284. 1803. 10. Nuttall Gen. N. Am. Pl. 1*302. 1818. 11. Elliott Sk. Bot. S. C. and Ga. 1:542. 1821. 12. Hall Pl. Texas 9. 1873. 13. Ridgway Proc. U. S. Nat. Mus. 65. 1882. 14. Chapman Fl. Sou. U. S. 131. 1897.
Plant seldom becoming a true tree, usually, however, forming a small but distinct trunk with a twiggy, bushy top; bark thin, dark reddish-brown, slightly furrowed or roughened, scaly; branches slender, usually zigzag with long, thin thorns or spine-like branchlets; branchlets slender, zigzag, glabrous, glossy, bright red; lenticels few, scattered, yellowish, raised.
Winter-buds small, obtuse, free, brownish; leaves folded upward, lanceolate or oblong-lanceolate, pointed at both ends, thin, membranaceous, margins closely and finely serrate with minute teeth, tipped with glands; upper surface glabrous, lustrous, bright green, lower surface glabrous or pubescent in the axils of the veins, dull, two-thirds inch wide and from one to two inches long; petioles one-half inch long, slender, glabrous or tomentose, bright red with two red glands near or on the base of the leaf; stipules one-half inch long, narrow-lobed, serrate with gland-tipped teeth.
Flowers appearing with or before the leaves, small, less than one-half inch across, very numerous; umbels sub-sessile, two to four-flowered, from lateral spurs or buds; pedicels glabrous, slender, one-half inch in length; calyx-tube campanulate, glabrous; calyx-lobes obtuse, glabrous outside, margins ciliate, inner surface pubescent, reflexed; petals creamy in the bud, obovate, apex rounded, narrowing into a claw at the base; filaments and pistils glabrous, the latter shorter than the stamens.
Fruit ripening early; spherical or ovoid, three-quarters inch in diameter, bright red, sometimes yellow, glossy, with little or no bloom; dots numerous, very conspicuous; skin thin; flesh tender, juicy, yellow, subacid; quality rather poor; stone small, clinging, ovoid, turgid, slightly roughened, cherry-like, edges rounded, the dorsal one grooved.
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 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, it is supposed to have escaped from their semi-cultivated plantations. Bailey 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. 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, one of which, the Indian plum, must have been the fruit of the present discussion. Bruce quotes 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.
"The Chicasaw plumb I think must be excepted, for though certainly a native of America, yet I never saw it wild in the forest, but always in old deserted Indian plantations: I suppose it to have been brought from the S. W. beyond the Mississippi, by the Chicasaws." Bartram Travels Through North and South Carolina, Georgia, East and West Florida, etc. 38. 1793.
PRUNUS ANGUSTIFOLIA WATSONI (Sargent) Waugh1
1. Waugh Vt. Sta. An. Rpt. 12:239. 1899. 2. Bailey Cyc. Am. Hort. 1450 fig. 1901. P. watsoni. 3. Sargent Gar. and For. 7:134, fig. 1894. 4. Waugh Bot. Gaz. 26:53. 1898. 5. Bailey Ev. Nat. Fr. 218. 1898.
Shrub four to ten feet high; branches slender, short-jointed, zigzag, reddish-brown; branchlets at first bright red and lustrous, later becoming brownish-red or sometimes ashy-gray; lenticels few and light-colored; leaves small, ovate, apex acute, base rounded or cuneate, margins finely crenulate; upper surface glabrous, shining, lower surface paler, glabrous; petioles reddish, one-half inch in length, biglandular at the apex.
Flowers in fascicles of two to four, borne with or before the leaves and in great abundance; calyx cup-shaped, the lobes acute, eglandular, ciliate on the margins, pubescent on the inner surface; petals white, obovate, contracted into a claw at the base; filaments glabrous, anthers reddish, style slender, exserted; pedicels one-quarter inch long.
Fruit two-thirds inch in diameter, globose, sometimes oblong, orange-red, bloom-less, handsome; skin thin, rather tender; flesh yellow, juicy, tender, pleasant flavor; of comparatively high quality; stone somewhat turgid, compressed at the apex, thick-walled, rounded on the ventral and sometimes on the dorsal suture.
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. Prom 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 gives the following interesting sketch of the use to which this plum has been put in Kansas:
"Early settlers in Kansas, before their own orchard plantings came into bearing, used to find the sand plums well worth their attention. In July and August everybody for fifty miles back from the Arkansas sand hills used to flock thither to pick, and it was an improvident or an unlucky family which came off with less than four or five bushels to can for winter. Whole wagon loads of fruit were often secured, and were sometimes offered for sale in neighboring towns.
" The fruit gathered from the wild trees was of remarkably fine quality, considering the conditions under which it grew. The plums were quite uniformly large— I would say from memory that they often reached three-fourths of an inch to an inch in diameter. They were thin-skinned and of good flavor, not having the unpleasant astringency of the wild Americana plums, which were also sometimes gathered. They were excellent for canning and made the finest of jelly.
" Naturally, the settlers who went every year to the sand hills for plums brought back trees to plant in the gardens they were opening. Almost every farm within the range mentioned above had a few or many of the dwarf trees growing. Some of these were fruitful and worth their room, but most of them have now died out, or are neglected and forgotten. This is because people have paid no attention to their selection, propagation and cultivation. Further than this, however, the sand plum has often failed signally to come up to its record when transferred to cultivation. It seems not to adapt itself readily to a wide diversity of soils and conditions."
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
Plant a small tree, attaining a height of twenty-five feet; trunk small but well-defined; branches spreading, bushy, sometimes armed with spinescent branchlets; young wood slender, more or less zigzag, usually glabrous, glossy, reddish but approaching a chestnut-brown; lenticels few, scattered, yellowish, raised.
Leaves oblong, oval-lanceolate or rarely slightly obovate-lanceolate, one and one-fifth to two and one-fifth inches long, three-quarters to one inch broad, gradually narrowed at the base, acute at the apex; margins very minutely glandular-serrate; upper surface glabrous and somewhat lustrous; lower surface paler, glabrous or sparingly hairy along the midrib and in the axils of the lateral veins; petioles slender, usually reddish, about one-half inch long, pubescent along the upper side, eglandular or sometimes with one or two glands at the apex; stipules small, linear and glandular-dentate.
Flowers appearing from early in March and before the leaves in the South, to the middle of April and with the leaves in the North, in dried specimens about one-half inch broad; pedicels three-eighths to one-half inch long, glabrous; calyx campanulate, the tube glabrous; calyx-lobes usually shorter than the tube, oblong and obtuse, glabrous on the outer surface, glabrous or sometimes sparingly pubescent on the inner, the margin ciliate, eglandular; petals obovate, gradually narrowed toward the base, erose or entire toward the apex.
Fruit globose or sub-globose, varying from red to yellow, usually with a light bloom; stone about one-half inch long, two-fifths inch broad, turgid, ovoid to elliptic-oblong, obscurely pointed at the apex or sometimes slightly obtuse, truncate or obliquely truncate at the base, grooved on the dorsal edge, ventral edge with a narrow, thickened and slightly grooved wing, the surfaces irregularly roughened.
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 Wight and Hedrick
Prunus angustifolia. 1. Bailey Cornell Sta. Bul. 38:58. 1892 (in part). 2. Ibid. Ev. Nat. Fr. 191-194. 1898 (in part). 3. Waugh Vt. Sta. An. Rpt. 10:99, 105. 1897 (in part).
Prunus hortulana. 4. Bailey Cornell Sta. Bul. 38:48. 1892 (in part). 5. Waugh Vt. Sta. An. Rpt. 10:99, 103-105. 1896-97 (in part).
Tree medium to large, from twenty to thirty feet in height; trunk six to ten inches in diameter; bark grayish-brown, shaggy, furrowed; branches spreading, rather slender, zigzag, little or not at all thorny; branchlets slender, zigzag, reddish, lustrous, glabrous; lenticels numerous, large, raised.
Winter-buds small, short, obtuse, usually free; leaves one and one-quarter inches wide by four inches long, lanceolate to oblong-lanceolate, sometimes broadly so, somewhat folded, apex acute or tapering, usually rounded at the base, texture thin, margins closely and finely serrate, teeth with small, dark red glands; upper surface bright green, glabrous, lustrous; lower surface dull green, pubescence sparse along the midrib and veins or sometimes tufted in the axils; petioles slender, about three-quarters of an inch long, pubescent on the upper surface, reddish, usually with two glands at the base of the leaf-blade; stipules linear, glandular, serrate.
Flowers appearing before or with the leaves, season of blooming late, about three-quarters inch across, odor sometimes disagreeable; borne on lateral spurs and buds, two or four flowers in a cluster; pedicels one half inch long, slender, glabrous; calyx-tube campanulate, glabrous, obscurely nerved, about one-fourth length of the pedicel; calyx-lobes as long as tube, ovate-oblong, obtuse at the apex, usually glabrous outside, pubescent inside at least toward the base, glandular-ciliate, erect; petals one-third inch long, white, creamy in the bud, oval or obovate, margins slightly erose, abruptly tapering into a claw, sometimes pubescent; stamens about twenty in number, equal to or shorter than the petals; filaments glabrous; anthers yellow or sometimes tinged red; pistils glabrous, shorter than the stamens.
Fruit ripening early; globose or oval, shortest diameter about an inch, bright currant-red, rarely yellow; bloom thin; dots few or numerous, whitish, large or small, always conspicuous; cavity shallow, narrow; suture a line; apex rounded or slightly depressed; flesh light to dark yellow, juicy, soft or melting, fibrous, sweetish, sour at the pit, aromatic; good; stone clinging to the flesh, varying from about one-half inch in length in the wild fruits to at least three-quarters inch in cultivated varieties, turgid, oval, prolonged and pointed at the apex, usually obliquely truncate at the base, more or less roughened, grooved on the dorsal edge, thick-margined and markedly grooved on the ventral one.
The description of this species is based on both wild and cultivated material, and the variety Arkansas may be considered as a typical 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.
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 irovciPrunus 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.
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
I. Marshall Arbust. Am. 112. 1785. 2. Wangenheim Amer. 103. 1787. 3. Michaux Fl. Bor. Am. 1:284. 1803. 4. Pursh Fl. Am. Sept. 332. 1814. 5. Nuttall Gen. N. Am. Pl. 1:302. 1818. 6. Elliott Sk.,Bot. S. C. and Ga. 1:543. 1821. 7. Torrey and Gray Fl. N. Am. 1:408. 1840. 8. Torrey Fl. N. Y. 1:194. 1843. 9. Emerson Trees of Mass. 449. 1846. 10. Bailey Cornell Sta. Bul. 38:75, fig. No. 9. 1892. 11. Waugh Vt. Sta. An. Rpt. 12:234. 1899. 12. Bailey Cyc. Am. Hort. 1449, fig. 1901.
P. littoralis. 13. Bigelow Fl. Bost. Ed. 2:193. 1824.
P. pubescens. 14. Torrey Fl. U. S. 469. 1824.
Cerasus pubescens. 15. Seringe DC. Prodr. 2:538. 1825. 16. Beck Bot. Nor. and Mid. Ut S. 96. 1833.
Shrub four to ten feet high, sometimes a low tree under cultivation; main branches decumbent and straggling or upright and stout; bark dark brown or reddish, more or less spiny, often warty; branchlets slightly pubescent at first, becoming glabrous, dark reddish-brown, straight or slightly zigzag and rather slender; lenticels few, small, dark.
Winter-buds small, long, acute, with small reddish scales; leaves oval or obovate, short-acute or nearly obtuse at the apex, rounded or nearly acute at the base, margins closely and evenly serrate, thinnish or thickish and somewhat leathery; upper surface glabrous, dull green, lower surface paler and more or less pubescent; petioles less than one-half inch long, stout, tomentose or glabrous; glands two, sometimes more, at the base of the leaves.
Flowers small, appearing before the leaves but the latest of any of the hardy plums; borne in three-flowered umbels closely set along the rigid branches; calyx-tube campan-ulate, tomentose; petals white, sometimes pinkish, sub-orbicular, narrowed into a claw at the base; pedicels short, slender, stiff, tomentose.
Fruit maturing in late summer in Massachusetts; one-half inch in diameter, globose, slightly flattened at the ends; cavity shallow, borne on a slender pedicel more than one-half inch in length, usually dark purple with a heavy bloom but variable, sometimes red or less frequently yellow; skin thick, tough and acrid; flesh crisp, juicy, sweetish; stone free from the flesh, small, turgid, pointed at both ends, cherry-like, acutely ridged on one and grooved on the other edge.
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 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: " 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, 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.
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. 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." 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.
This plum has a number of qualities that commend it to the fruitgrower. 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:
"I first began raising Prunus maritima about 1887-- twenty-two years ago-- collecting myself and having specimens sent me all the way from the coast of Labrador to South Carolina, the finest of which were obtained from the eastern coast of Massachusetts. Among the seedlings, of which I raised and fruited several hundred thousands, were yellow, red, purple and almost black ones, early and late, round, oval, oblate and flattened, with big stones and little stones, free stone and cling stone, and much variety in productiveness and growth of the young bushes, but not one of them the first two or three generations were very much increased in size- probably the largest being about the size of a cranberry or a small hazelnut- and none of them of very exceptional quality, though their habit of blooming late was a tremendous advantage, as they invariably escaped our spring frosts. This, with their unusual hardiness induced me to continue experimenting with them. Finally after some ten years I obtained a very delicious variety, about an inch in length and three-quarters of an inch in diameter, tree much increased in size, larger foliage and more productive and producing enormous quantities of most delicious fruit. From this I raised a great many thousand, almost as good and a few of them even better, several hundred of which have been selected and are now bearing on my Sebastopol place. Some of these improved seedling trees grow five to ten times as large as the ordinary Maritima, with larger leaves and in every possible way improved. My greatest success with this species (and one of the most striking occurrences in my work with plums) was produced by pollinating one of the somewhat improved Maritimas with Prunus triflora.
"The very first generation, a plum was produced which is an astonishing grower for a Maritima- almost equal to the Triflora, with large, broad glossy foliage of almost the exact shape of the Maritima, Maritima blossoms, and fruit weighing nearly one-quarter of a pound each, with an improved superior Maritima flavor, Maritima pit in form, but enlarged. The most singular peculiarity of this plum, which is so enormous, is that the trees commence to bloom about with the Triflora and bloom and bear fruit all summer, so that blossoms, young fruit and the enormous deep red ripening fruit can be seen on the trees at the same time."
21. PRUNUS GRAVESII Small
1. Small Torrey Bot. Club Bul. 24:44, Pl. 292. 1897. 2. Britton and Brown N. Am. Trees 2:249. 1897. 3. Robinson and Fernald Gray's Man. Ed. 7:498. 1908.
Shrub low, slender, attaining a height of four feet; main trunk much branched, with dark, rough bark; branches ascending, slender, leafless, unarmed; branchlets of the season puberulent. Leaves oval-orbicular, orbicular or slightly obovate, rounded, retuse or apiculated at the apex, base truncate or at least obtuse, margins sharply serrate or crenate-serrate; upper surface sparingly pubescent or glabrous, lower surface pubescent, especially on the veins.
Flowers white, one-half inch broad; borne in two or three-flowered, lateral umbels, appearing with the leaves; calyx-tube campanulate, pubescent; petals sub-orbicular, abruptly narrowed at the base; pedicels stout, stiff, pubescent.
Fruit maturing in September; globose, one-half inch in diameter, nearly black, with a light bloom, acid and astringent; stone broadly oval, rounded at the apex, acute at the base.
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: (i) 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 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
I. Koehne Dent. Dend. 311. 1893. 2. Sargent Gar. and For. 7:184, 187 fig. 1894. 3. Bailey Cyc. Am, Hort. 1450. 1901.
Shrub four or five feet high; branches dense and twiggy; stems sometimes armed with slender spines; bark separating in large, loose scales; branchlets stout, slightly zigzag, reddish-brown becoming dark brown.
Winter-buds obtuse, three-lobed at maturity; leaves oblong-ovate, thin and firm, acuminate, long-pointed, two and one-half to three inches long, two-thirds inch broad, unequally cuneateor rounded at the base; margins closely serrate with incurved, calloused or rarely glandular teeth; upper surface glabrous, light green, lower surface paler and pilose; petioles slender, slightly grooved, puberulous, one-half inch long; glands two, large, at the apex of the petiole.
Flowers appearing after the leaves; borne in three or four-flowered fascicles on stout pedicels one-half inch long; calyx-tube turbinate; lobes puberulous on the outer surface, with thick tomentum, often tipped with red on the inner surface; petals narrowly obovate, rounded at the apex, narrowing at the base into slender claws, white or tinged with pink; stamens orange, exserted; style glabrous, thickened at the apex into a truncate stigma.
Fruit globose, an inch in diameter, deep red with a heavy bloom; skin thick; flesh yellow, juicy, of good flavor; stone flattened, oval, slightly rugose, deeply grooved on the dorsal and ridged on the ventral edge.
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 Plains, Massachusetts, and the City parks at Rochester, New York, it seems well worth cultivating. Mr. J. W. Kerr writes of it as follows:
"I have P. orthosepala fruiting here, and with me its fruit is exceptionally fine in quality, sparingly produced attributable I believe to the fact that no variety stands near enough to it for proper inter-pollination. The trees are rather dwarfish in habit, close-headed, with fine clean foliage. The fruit is globular in form; size equal to fair specimens of Hawkeye or Wyant; skin a greenish-yellow, almost entirely covered with deep red."
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 orthosepala. 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 orthosepala was grown may be an error.
23. PRUNUS GRACILIS Engelmann and Gray
1. Engelmann and Gray Bost. Jour. Nat. Hist. 5:243. 1845. 2. Torrey Pac. R. Rpt. 4:83. 1854. 3. Britton and Brown III. Fl. 2:249, fig. 1897.
P. ckicasa var. normalis. 4. Torrey and Gray Fl. N. Am. 1:407. 1840. P. normalis 5. Small Fl. S. E. U. S. 572. 1903.
Shrub low, attaining a height of five or six feet; branches many, straggling, more or less spiny; branchlets at first densely tomentose or soft-pubescent, becoming glabrous; leaves small, ovate-lanceolate or oval, margins finely and evenly serrate, rather thick, texture harsh and firm; upper surface dark green, glabrous or nearly so at maturity, lower surface paler, soft-pubescent becoming nearly glabrous; petiole short and stout.
Flowers white, small, appearing before the leaves; borne in sessile, several-flowered umbels; pedicels short, slender, soft-pubescent.
Fruit globose or oval, very small, not more than one-half inch in diameter, variable in color, mostly in shades of red; stone turgid, nearly orbicular, pointed at both ends.
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 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
1. Scheele Linnaea 21:594. 1848. 2. Gray Pl. Wright. 1:67. 1852. 3. Hall Pl. Texas. 9 1873. 4. Coulter Cont. U. 5. Nat. Herb. 2:101. 1891. 5. Waugh Bot. Gaz. 26:50-52. 1898. 6. Bailey Ev. Nat. Fr. 223. 1898.
Shrub three to seven feet high; branches angular, smooth, shining, ash-colored, rough; lenticels small, crowded; leaves oblong-ovate or sometimes ovate, rarely lanceolate, apex acute, margins coarsely or doubly serrate, glabrous above and sparingly pubescent below; petioles glandular, grooved, pubescent; flowers in lateral umbels, in pairs or several-flowered; fruit about one-half inch in diameter, oblong-oval, cherry-red; skin thick, smooth and tough, acid.
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." * 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.