Leaves lanceolate to ovate-lanceolate, acuminate and long-pointed at apex, cuneate or rounded at base, often slightly falcate, finely serrate, glabrous, dark green and lustrous above, pale or glaucous below, 1½′—3′ long, about ½′ wide, on vigorous summer shoots often 6′ or 7′ long and 1½′ wide; petioles slender, glabrous, glandular at apex, ¼′ in length, or on summer shoots stout and 1′—1½′ long; stipules reniform, caducous. Flowers: aments terminal on leafy puberulous branchlets, narrow-cylindric, 2½′—3′ in length; scales pale pubescent, those of the staminate ament lanceolate-acuminate to obovate and rounded at apex and entire, those of the pistillate ament obovate and usually dentate near the apex; stamens 5—9; filaments hairy below the middle; ovary rather abruptly narrowed above the middle and acuminate, long-stalked; style short with slightly emarginate lobes. Fruit light red-brown, ¼′ long; pedicels about 1/16′ in length.
Distribution. Valley of the Yukon River near Dawson, Yukon, Vancouver Island, and southward near the coast of Washington and Oregon, and on the western slope of the Sierra Nevada and on the coast ranges to southern California, ranging from the sea-level to altitudes of 8500° on the southern Sierra Nevada; in New Mexico (Glenwood, Soccoro County, and Santa Fé, Santa Fé County); in Colorado (Buena Vista, Chaffee County, _Alice Eastwood_). Passing into var. _caudata_ Sudw., distinguished by its caudate-acuminate leaves green on both surfaces, and by its bright yellow or orange-yellow branchlets, and ranging from northeastern Oregon and eastern Washington through Idaho, and from northern Wyoming to southern Colorado, Utah and Nevada.
A variety (var. _lancifolia_ Bebb), differing from the typical _S. lasiandra_ in the gray or rusty villose pubescence covering the branchlets during their first and sometimes their second season and the lower surface of the young leaves, is distributed from Dawson in the valley of the Yukon River southward to the valley of the upper Nesqually River, Washington, to the valley of the Willamette River (Salem, Oregon), to Santa Cruz, Santa Cruz County, and to the San Bernardino Mountains, California.
Leaves ovate-lanceolate, or narrow lanceolate (f. _angustifolia_ Anders.), acuminate and long-pointed at apex, cuneate or rounded at base, finely serrate, 3′—5′ long, 1′—1½′ wide, covered when they unfold with scattered pale caducous hairs, at maturity coriaceous, smooth and lustrous, dark green above, paler below, with a broad yellow midrib, and slender primary veins arcuate and united near the margins; petioles stout, yellow, puberulous, glandular at the apex, with several dark or yellow conspicuous glands, ¼′—½′ long; stipules nearly semicircular, glandular-serrate, membranaceous, ⅛′—¼′ wide, often persistent during the summer. Flowers: aments erect, tomentose, on stout puberulous peduncles terminal on short leafy branchlets, the staminate oblong-cylindric, densely flowered, about 1½′ in length, the pistillate slender, elongated, 1½′—2′ long, often persistent until late in the season; scales oblong or obovate, rounded, entire, erose or dentate at apex, light yellow, nearly glabrous or coated on the outer surface with pale hairs, often ciliate on the margins; stamens usually 5, with elongated free filaments slightly hairy at base; ovary narrowly cylindric, long-stalked, elongated, glabrous, with nearly sessile emarginate stigmas. Fruit: cylindric, lustrous, about ⅓′ long.