54. Salix wolfii Bebb in J. T. Rothrock, Rep. U. S. Geogr. Surv., Wheeler. 241. 1879.
Idaho willow
Plants 0.1-2 m. Stems: branches red-brown, violet, yellow-gray, or yellow-brown, pubescent or pilose to glabrescent; branchlets yellowish, yellow-brown, red-brown, or yellow-green, sparsely or moderately densely pubescent, or densely long-silky, (inner membranaceous bud-scale layer free, separating from outer layer). Leaves: stipules rudimentary or foliaceous on early ones, foliaceous on late ones, apex rounded, acuminate, or acute; petiole convex to flat, or shallowly grooved adaxially, 3-12 mm, pubescent, long-silky, or villous adaxially; largest medial blade narrowly oblong, narrowly elliptic, elliptic, or oblanceolate, 26-56 × 8-16.5 mm, 2.5-3.7-5.6 times as long as wide, base cuneate, convex, or rounded, margins flat, entire, apex acute, acuminate, or convex, abaxial surface not glaucous, pubescent, short-silky, or villous, hairs appressed or spreading, straight or wavy, adaxial dull, sparsely to densely silky or villous; proximal blade margins entire; juvenile blade yellowish green, densely short- or long-silky or villous abaxially, hairs white. Catkins flowering as leaves emerge; staminate stout or subglobose, 9.5-16 × 6-12 mm, flowering branchlet 1-5.5 mm; pistillate moderately or very densely flowered, stout, subglobose or globose, 8.5-38 × 5-12 mm, flowering branchlet 1-11 mm; floral bract brown, black, or bicolor, 0.8-2 mm, apex rounded or acute, abaxially hairy, hairs wavy, straight, or curly. Staminate flowers: (abaxial nectary 0-0.2 mm), adaxial nectary oblong, 0.4-1.1 mm, (nectaries distinct); filaments distinct, glabrous; anthers yellow, 0.3-0.5 mm. Pistillate flowers: adaxial nectary oblong, ovate, or flask-shaped, 0.4-1.1 mm, shorter to longer than stipe; stipe 0.2-0.9 mm; ovary pyriform, glabrous or hairy, beak gradually tapering to or slightly bulged below styles; ovules 8-16 per ovary; styles 0.3-1 mm; stigmas flat, abaxially non-papillate with rounded or pointed tip, or slenderly or broadly cylindrical, 0.24-0.3-0.4 mm. Capsules 3-5 mm.
Varieties 2 (2 in the flora): w United States.