Deciduous shrubs and trees. Twigs slender or moderate, sub-terete or somewhat angled at the nodes, sometimes sharp-pointed; pith round or angled, pale or brown, continuous. Buds solitary or multiple, sessile, subglobose or ovoid, with about 6 visible scales. Leaf-scars alternate, half-round or elliptical, small; bundle-traces 3, usually minute; stipule-scars or vestiges present.
Fig. 156. Prunus maritima.
Fig. 157. Prunus alleghaniensis.
Terminal bud present
b. Twigs red or green; buds hairy
b. Twigs brown or gray
c. Twigs more or less velvety
c. Twigs glabrous
d. Buds dull brown, ovoid; scales rough
d. Buds clear brown or glossy
e. Buds small, 2-4 mm. long
f. Buds 4 mm. long; scales chestnut-brown, keeled
f. Buds 2 mm. long; scales red-brown, ciliate
e. Buds larger, 5-7 mm. long
f. Buds ovoid-fusiform, glossy
f. Buds round-ovoid, duller or darker
Terminal bud deciduous
b. Buds about as long as thick
b. Buds elongated
c. Twigs velvety, becoming glabrate
c. Twigs glabrous
d. Armed with spine-tipped twigs
e. Buds 3-6 mm. long; small tree
e. Buds 2 mm. long; usually a low straggling shrub
e. Buds large, sometimes 10-12 mm. long; tree
e. Buds small, 2 mm. long; shrub
1. P. maritima Marsh. Beach Plum. Low and straggling or ascending shrub 0. 3-2. 5 m. high, densely branched; twigs at first pubescent, becoming glabrate; buds acute, velvety. Sandy soil, mostly in the coastal plain, Maine to Delaware (Fig. 156).
Fig. 158. Prunus americana.
Fig. 159. Prunus hortulana.
Fig. 160. Prunus angustifolia.
Fig. 161. Prunus persica.
Fig. 162. Prunus pensylvanica.
Fig. 163. Prunus avium.
2. P. allegheniensis Porter. Alleghany Plum. A straggling shrub 1-5 m. high, sometimes armed with sharp-pointed twigs; bark brown; twigs reddish-brown. Dry soil, mostly in the mountains, Connecticut to Virginia and West Virginia (Fig. 157).
3. P americana Marsh. Wild Plum. A shrub or tree 3-10 m. high, bark dark, shaggy; twigs orange-brown, sharp-pointed, glabrous; buds acute, 3-6 mm. long, chestnut-brown. Thickets, Florida to New Mexico, north to New England, Ontario, Manitoba, Wyoming, and Utah; also in Mexico (Fig. 158).
4. P. hortulana Bailey. Wild Goose Plum. A small unarmed tree, 10 m. high or less; twigs glabrous, reddish-brown; buds obtuse, chestnut-brown. Bottomlands, Indiana to Iowa, south to Alabama and Oklahoma (Fig. 159).
5. P. angustifolia Marsh. Chickasaw Plum. A shrub 2-5 m. high, not very thorny; buds half covered by the ciliate leaf-cushion; twigs slender, red, lustrous. Dry thickets, Florida to Texas, north to New Jersey and Missouri (Fig. 160).
6. P. persica (L.) Batsch. Peach. A small tree, up to 8 m. tall, the reddish or green twigs glabrous; buds hairy. Introduced from Asia, much cultivated, and frequently escaped (Fig. 161).
7. P. pensylvanica L. f. Fire Cherry. Pin Cherry. Bird Cherry. A tree 6-20 m. high, with light red-brown bark; twigs glabrous, slender, reddish, shining. Dry woods, recent burns and clearings, Labrador to British Columbia, south to Colorado, South Dakota, Iowa, and in the mountains to North Carolina (Fig. 162).
8. P. avium L. Sweet Cherry. A large tree, sometimes 20 m. high, with pyramidal crown and reddish-brown bark; twigs rather thick, buds large, glossy, ovoid-fusiform. Introduced from Eurasia, often spread from cultivation and naturalized (Fig. 163).
9. P. cerasus L. Sour Cherry. Tree to 24 m. high, of pyramidal habit; branchlets rather thick; buds large, dull, round-ovoid. Introduced from Asia, spread from cultivation and naturalized (Fig. 164).
10. P. mahaleb L. Mahaleb. Perfumed Cherry. Small tree to 10 m. high, with open branching; bark aromatic; twigs tomentulose; buds round-ovoid, spreading. Introduced from Eurasia, spread from cultivation and naturalized (Fig. 165).
Fig. 164. Prunus cerasus.
Fig. 165. Prunus mahaleb.
Fig. 166. Prunus serotina.
Fig. 167. Prunus virginiana.
11. P. serotina Ehrh. Wild Black Cherry. A tree 20-35 m. tall, the trunk 10-15 dm. in diameter; bark on old trees very rough and black, on the branches smoother and gray-brown; inner bark strongly and unpleasantly scented; twigs reddish-brown, buds about 4 mm. long. Woods and open fields, Florida to Texas and Mexico, north to New Brunswick, Minnesota and North Dakota (Fig. 166).
12. P. virginiana L. Choke Cherry. A tall shrub or small tree, 15 m. high, with grayish bark, the inner layers with a rank disagreeable odor; twigs glabrous. Thickets, Newfoundland to Saskatchewan, south to North Carolina, Missouri and Kansas (Fig. 167).