This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Salix exigua Nutt. Sylva 1: 75. 1842.
S. fluviatilis exigua Sargent, Silva 9: 124. 1896.
A shrub or small tree up to 20° high, the twigs often permanently pubescent. Leaves linear to linear-oblanceolate, small, usually not more than 3' long and 3" wide, short-petioled, entire, acute at each end, often permanently silky-hairy; stipules early deciduous; aments borne on lateral leafy branches, 2' long or less; bracts obtuse, pubescent, deciduous; stamens 2, the filaments hairy below; capsule silky when young, becoming about 2 1/2" long and glabrous when mature, very short-stalked; style very short, shorter than the stigmas.
River and lake shores, Nebraska to Wyoming, British Columbia, Texas and California.
A much-branched shrub, 2°-12° high, forming thickets, or sometimes a slender tree, 20°-30° tall, and with a trunk 1° in diameter, the young foliage silky-pubescent, the mature leaves glabrous, or nearly so, those of seedlings pinnately dentate or lobed. Leaves linear-lanceolate or linear-oblong, 2 1/2'-4' long, 1 1/2"-5" wide, acuminate, remotely denticulate with somewhat spreading teeth, short-petioled, bright green; petioles not glandular; stipules minute or none; aments on short, leafy branches, linear-cylindric, the staminate dense, 1'-1 1/2' long, the pistillate looser, about 2' long in fruit; bracts deciduous; stamens 2; filaments pubescent, distinct; stigmas broad, sessile; capsule ovoid-conic, glabrous or silky, about 2" long.
Along streams and lakes, Quebec to Athabasca, Virginia, Kentucky and Texas. Has been confused with Salix fluvia-tilis Nutt. Wood soft, reddish-brown; weight per cubic foot 31 lbs. Long- or Narrow-leaf willow. Red or white willow. Osier- or shrub-willow. April-May.
Salix Wheeleri (Rowlee) Rydb., of lake and river shores from New Brunswick to Illinois, differs in having the leaves permanently silky.
Salix alba L. Sp. PI. 1021. 1753.
Salix vitellina L, Sp. PI. Ed. 2, 1442. 1763.
A large tree, sometimes 900 tall and a trunk diameter of 8°; bark gray, rough; twigs brittle at the base. Leaves lanceolate or oblong-lanceolate, acute or acuminate, narrowed at the base, serrulate, silky-pubescent on both sides when young, less so and pale or glaucous beneath when mature, 2-4 1/2' long, 4"-8" wide; stipules ovate-lanceolate, deciduous; petioles 2"-4" long, glandless or sparingly glandular; aments on short lateral leafy branches; stamens 2; filaments distinct, pubescent at the base; pistillate aments linear-cylindric, 1 1/2'-2 1/2' long; stigmas nearly sessile; capsule ovoid, acute, glabrous, short-pedi-celled or sessile.
In moist soil, especially along streams, Nova Scotia to Ontario, North Carolina and Iowa, escaped from cultivation. Native of Europe. Composed of several races, with twigs green to yellow. Duck-willow. April-May.