94. Salix tweedyi (Bebb ex Rose) C. R. Ball, Bot. Gaz. 40: 377. 1905.
Tweedy’s willow Tweedy’s willow
Salix barrattiana Hooker var. tweedyi Bebb ex Rose, Contr. U.S. Natl. Herb. 3: 572. 1896
Plants 1-3 m. Stems: branches red-brown, not glaucous, villous to glabrescent; branchlets yellow-brown, (sometimes strongly glaucous), pilose or moderately densely villous, (buds caprea- or arctica-type, scale inner membranaceous layer free, separating from outer layer). Leaves: stipules (sometimes marcescent), foliaceous, (3.5-10-23 mm, 1-1.4-2.8 times as long as wide, usually lanceolate, ovate, or suborbiculate, (pleated when pressed), apex rounded, convex, or acute; petiole shallowly grooved adaxially, 3-11.3-26 mm, villous adaxially; largest medial blade elliptic to broadly elliptic, 36-65-100 × 17-35.5-85 mm, 1.1-1.9-2.9 times as long as wide, base convex, rounded, subcordate, or cordate, margins thickened, serrulate or spinulose-serrulate (sometimes teeth absent, margins with spherical glands), apex acuminate, acute, or convex, abaxial surface glaucous or not, pilose or villous, hairs curved, adaxial dull, pilose or villous to glabrescent; proximal blade margins entire (glands only) or serrulate; juvenile blade green, glabrous, pilose, or moderately densely villous abaxially, hairs white. Catkins flowering before leaves emerge; staminate stout, 39-56 × 14-22 mm, flowering branchlet 0-2 mm; pistillate densely flowered, stout, 39-70(-110 in fruit) × 13-22 mm, flowering branchlet 0-2 mm; floral bract dark brown, 1.8-4 mm, apex acute or rounded, abaxially sparsely hairy, hairs straight or wavy. Staminate flowers: adaxial nectary oblong, 0.6-1.2 mm; filaments distinct, glabrous or hairy basally; anthers yellow or purple turning yellow, 0.6-1 mm. Pistillate flowers: adaxial nectary oblong, narrowly oblong, or square, 0.5-1 mm, (unlobed), shorter to longer than stipe; stipe 0.4-1.5 mm; ovary pyriform, beak gradually tapering to styles; ovules 18-30 per ovary; styles 1.1-2.8 mm; stigmas slenderly cylindrical, 0.32-0.53-1 mm. Capsules 4-7 mm.
Flowering Jul. Subalpine and alpine, streamsides and bottoms, lakeshores, marshes, spruce bogs, talus slopes, tundra, quartzite, granite, or, sometimes, limestone substrates; 1400-4000 m; B.C.; Idaho, Mont., Wash., Wyo.