S. amygdaloìdes.
2. Sàlix amygdaloìdes, Anderson. (Western Black Willow.) Leaves 2 to 4 in. long, lanceolate or ovate-lanceolate, attenuate-cuspidate, pale or glaucous beneath, with long slender petioles; stipules minute and soon falling. A small tree, 10 to 40 ft. high, from central New York westward. It is the common Black Willow of the streams of Ohio to Missouri.
S. frágilis.
3. Sàlix frágilis, L. (Brittle Willow. Crack-willow.) Leaves lanceolate, taper-pointed, smooth, glaucous beneath (slightly silky when young), serrate throughout; stipules half heart-shaped, usually large. Branches smooth and polished, very brittle at base. A tall (50 to 80 ft. high) handsome Willow, with a bushy head and salmon-colored wood; cultivated from Europe for basket-work, and extensively naturalized. Many varieties, hybrids between this species and the next, are very common. Among them may be mentioned the following:
Var. decipiens, with dark-brown buds; var. Russelliana, with more slender, brighter, and more sharply serrate leaves, the annual shoots silky-downy toward autumn; var. viridis, with tough, pendulous branchlets, and firmer, bright green leaves.
S. álba.
4. Sàlix álba, L. (White Willow.) Leaves lanceolate or elliptical-lanceolate, pointed, serrate, covered more or less with white silky hairs, especially beneath; var. cærulea has nearly smooth leaves, at maturity of a bluish tint; stipules small and quite early deciduous. Catkins of flowers long and loose, on a peduncle; stamens usually 2; stigmas nearly sessile, thick, and recurved. May, June. A quite large tree, 50 to 80 ft. high, with thick, rough bark, usually having yellow twigs (var. vitellina); introduced from Europe and now quite common throughout. Branches very brittle at base.
