Nearly all of the early ripening horticultural varieties previously referred to Prunus angustifolia belong to Prunus angustifolia varians. The fruit of the sub-species appears to be superior to that of the species though scarcely equal to that of the other southern plums now cultivated. Hybrids between this form and Prunus munsoniana undoubtedly occur freely both in the wild state and under cultivation. The varieties Eagle and El Paso have probably originated in this way. Nearly all of the plums belonging to this species, some twenty in all, are tender to cold, none, so far as is known, succeeding in the North. African, Cluck, Jennie Lucas and Yellow Transparent may be named as representative varieties.
19. PRUNUS MUNSONIANA[139] Wight and Hedrick
PRUNUS MUNSONIANA
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.