Trees to 20 m tall. Trunk to 50 cm d.b.h.; bark gray-brown, scabrous. Young branches yellow-brown pubescent at first, soon glabrate, old ones conspicuously lenticellate. Buds shiny red-brown; scales 6–8, margin puberulous. Petiole 1–2.5 cm, sparsely villous; leaf blade pale green adaxially when old, 5–15 × 2.5–7 cm, brown pubescent at first, later pubescent only along veins, lateral veins 6–9-paired, together with reticulate veins slightly prominent abaxially, concave adaxially. Male flowers: stamens ca. 1 cm, glabrous, filaments ca. 1 mm. Female flower: ovary ca. 1 cm, glabrous. Samara 2.5–3.5 × 1–1.3 cm; stipe 2–5 mm, articulate at 1–3 mm pedicel. Seed 1.3–1.5 cm × ca. 3 mm. Fl. Mar–May, fr. Jun–Nov.
Trees to 20 m; bark gray-brown, ridged and furrowed; branchlets brown, hairy when young, becoming glabrate, pith septate. Leaves: petioles 1–2.5 cm; blades elliptical to ovate, 5–20 × 2.5–8 cm, base usually truncate to broadly cordate or cuneate, sometimes oblique, apex acuminate, surfaces hairy when young, soon glabrate; latex strands visible in carefully torn leaf. Staminate flowers: anthers 10–12 mm. Pistillate flowers: pistil 10–12 mm. Samaras brown, 25–32 mm, apex emarginate. Seeds 12–15 × 3 mm. 2n = 34.