Plants often forming clones by layering. Stems: branches dark gray-brown to yellow-brown, not glaucous, woolly in patches or floccose to glabrescent; branchlets yellow-brown to red-brown or gray-brown, densely (white) woolly or tomentose, sometimes floccose. Leaves: stipules rudimentary or foliaceous on early ones, late ones 2-3.6 mm, apex acute; petiole shallowly to deeply grooved adaxially, 3-10 mm, tomentose or densely (white) woolly adaxially (obscured by hairs); largest medial blade lorate, narrowly elliptic or oblanceolate, 47-103 × 5-20 mm, base convex or cuneate, margins strongly to slightly revolute, entire, or sinuate, apex acute or convex, abaxial surface glaucous (generally obscured by hairs), very densely to sparsely tomentose-woolly (cobwebby in age), hairs dull white, crinkled, adaxial dull or slightly glossy, moderately densely to sparsely tomentose, floccose, hairs dull white; proximal blade margins entire; juvenile blade yellowish green, very densely tomentose abaxially, hairs white. Catkins flowering as leaves emerge; staminate stout or subglobose, 17-39 × 8-16 mm, flowering branchlet 0.5-7 mm; pistillate densely to moderately densely flowered, stout or slender, 20-66 × 9-18 mm, flowering branchlet 1-24 mm; floral bract tawny or brown, 1.2-1.8 mm, apex rounded or acute, abaxially hairy, hairs straight to wavy. Staminate flowers: adaxial nectary narrowly oblong to oblong, 0.6-1 mm; filaments distinct or connate less than 1/2 their lengths; anthers purple turning yellow, ellipsoid, long-cylindrical, or globose, 0.4-0.6 mm. Pistillate flowers: adaxial nectary oblong, 0.4-1 mm; ovary pyriform, beak sometimes slightly bulged below styles; ovules 12-18 per ovary; styles 0.3-1.9 mm. Capsules 4-6 mm. 2n = 38.
Floodplains, marl bogs, fens, and meadows, calcareous substrates; at elevations up to 2,800 metres.
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