PRUNUS AMERICANA
1. Marshall Arb. Am. 111. 1785. 2. Eaton and Wright N. Am. Bot. 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. Nuttall 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. 1860. 10. Ridgway Proc. U. S. Nat. Mus. 65. 1882. 11. Sargent 10th Cen. U. S. 9:65. 1883 (in part). 12. Watson and Coulter Gray’s Man. Ed. 6:151. 1889 (in part). 13. Coulter Cont. U. S. Nat. Herb. 2:102. 1891. 14. Sargent Silva N. 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.[111] 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.