Evergreen shrubs or small trees. Twigs moderate or slender; pith small, continuous. Buds minute, solitary, sessile; terminal bud abortive. Leaves alternate (or seemingly opposite or in whorls of 3), entire. Leaf-scars half-round or shield-shaped; bundle-trace a transverse line; stipule-scars none. Fruit a small globose capsule persistent in winter.
Fig. 251. Kalmia latifolia.
Fig. 252. Kalmia angustifolia.
Fig. 253. Kalmia polifolia.
a. Large shrubs or small trees
K. latifolia ,
a. Low shrubs
b. Twigs terete
b. Twigs 2-edged
1. K. latifolia L. Mountain Laurel. Calico-Bush. Shrub or small tree, up to 10 m. high, generally much smaller; twigs glabrous; leaves elliptic to elliptic-lanceolate, 5-10 cm. long, acute or short-acuminate; capsule glandular, 5-7 mm. in diameter. Rocky woods, Florida to Louisiana, north to New England, Ohio, and Indiana (Fig. 251).
2. K. angustifolia L. Lambkill. Sheep-Laurel. Slender shrub up to 1.7 m. high; branches terete, strongly ascending; leaves evergreen, opposite or in whorls of three, flat, thin, oblong to elliptic-lanceolate, glabrous or puberulent, ferruginous when young. Acid soil, Labrador to Manitoba, south to Virginia, Georgia and Michigan (Fig. 252).
3. K. polifolia Wang. Pale-Laurel. Bog-Laurel. Slender straggling shrub to 7 dm. high, with 2-edged branches; leaves evergreen, opposite or in threes, firm,lanceolate or linear, 0.7-3. 5 cm. long, lustrous-green above, conspicuously whitened beneath. Peat bogs, Labrador to Alaska, south to Pennsylvania, Minnesota, Idaho, and Oregon (Fig. 253).