Tribe VII. POMEÆ. Carpels 2–5, enclosed in and coalescent with the fleshy or berry-like calyx, in fruit becoming a 2–several-celled pome. Trees or shrubs, with stipules free from the petiole.
a. Cells of the compound ovary as many as the styles (2–5), each 2- (rarely several-) ovuled.
16. Pyrus. Pome containing 2–5 papery or cartilaginous carpels.
17. Cratægus. Pome drupe-like, with 1–5 bony stones or kernels. Usually thorny.
b. Cells of the compound ovary becoming twice as many as the styles, each 1-ovuled.
18. Amelanchier. Pome usually of 5 carpels; each becomes incompletely 2-celled by a projection from its back; otherwise as Pyrus.
1. PRÙNUS, Tourn. Plum, Cherry, etc.
Calyx 5-cleft, the tube bell-shaped, urn-shaped, or tubular-obconical, deciduous after flowering. Petals 5, spreading. Stamens 15–20. Pistil solitary, with 2 pendulous ovules. Drupe fleshy, with a bony stone.—Small trees or shrubs, with mostly edible fruit. (The ancient Latin name.)
§ 1. PRUNUS proper (and Cerasus). Drupe smooth, and the stone smooth or somewhat rugged; flowers (usually white) from separate lateral scaly buds in early spring, preceding or coetaneous with the leaves; the pedicels few or several in simple umbel-like clusters.
1. P. Americàna, Marshall. (Wild Yellow or Red Plum.) Tree thorny, 8–20° high; leaves ovate or somewhat obovate, conspicuously pointed, coarsely or doubly serrate; very veiny, glabrous when mature; fruit nearly destitute of bloom, roundish oval, yellow, orange, or red, ½–{2/3}´ in diameter, with the turgid stone more or less acute on both margins, or in cultivated states 1´ or more in diameter, the flattened stone with broader margins; pleasant-tasted, but with a tough and acerb skin.—Woodlands and river banks, common.