Trees, 6–18 m. Stems: branches highly brittle at base, yellow-green, yellow-brown, or gray-brown, (highly glossy), glabrous; branchlets yellow-green, yellow-brown, or red-brown, (highly glossy), glabrous. Leaves: stipules rudimentary on early ones, rudimentary or foliaceous on late ones, (early deciduous to marcescent), apex acuminate or acute; petiole deeply grooved adaxially (margins usually touching), 6–8.6 mm, with pairs of spherical glands distally, glabrous or puberulent adaxially; largest medial blade hemiamphistomatous or hypostomatous, lanceolate, narrowly oblong, or narrowly elliptic, 60–120 × 14–30 mm, 3.6–6.5 times as long as wide, base convex or rounded, margins flat or slightly revolute, serrate, crenate, or crenulate, apex acute, acuminate, or caudate, abaxial surface (not glaucous), glabrous, adaxial slightly or highly glossy, glabrous; proximal blade margins entire; juvenile blade yellowish green or reddish, glabrous. Catkins: staminate 24–40 × 7–15 mm, flowering branchlet 12–15 mm; pistillate moderately densely flowered, stout, 24–35 mm, flowering branchlet 12–15 mm; floral bract (greenish or tawny), 0.8–1.3 mm, apex convex or rounded, entire or erose, abaxially hairy, hairs straight or wavy. Staminate flowers: abaxial nectary present, adaxial nectary oblong, 0.3–0.6 mm, nectaries distinct; filaments distinct or connate less than 1/2 their lengths, hairy at base; anthers ellipsoid, 0.4–0.5 mm. Pistillate flowers: adaxial nectary oblong or square, 0.3–0.6 mm, shorter than stipe; stipe 0.6–1.2 mm; ovary pyriform, beak gradually tapering to styles; styles connate, 0.3–0.5 mm; stigmas flat, abaxially non-papillate with rounded tip, or 2 plump lobes, 0.3–0.5 mm. Capsules 3–5 mm. 2n = 76.
