Description from Flora of China
Trees to ca. 25 m. Buds densely brown tomentose. Leaves 15-30 cm; petiole 5-8 cm; leaflets 7-9; petiolule 0.5-1.5 cm; leaflet blade ovate-lanceolate to elliptic, 8-12(-15) × (1-)2-4(-6) cm, thin leathery, adaxially glabrous, abaxially glabrous or pilose along midrib, base broadly cuneate, oblique, margin serrate, serrulate, or basally entire, apex caudate-acuminate; primary veins 10-12 on each side of midrib. Panicles terminal, spreading, many flowered, 20-30 cm. Flowers appearing after leaves. Pedicel 3-4 mm. Calyx cupular, 1-1.5 mm; teeth broadly deltate. Corolla white; lobes oblong, (1.5-)3-4 mm, obtuse. Stamens exceeding corolla lobes. Samara linear, 2-4 cm × 4-5 mm; wing decurrent to about middle or distal part of nutlet. Fl. Feb-Apr, fr. Jul-Oct. 2n = 46.
Dense forests, mixed woods of valleys, roadsides; sea level to 2600 m. Guangdong, Guangxi, Guizhou, Xizang, Yunnan, Zhejiang [Afghanistan, Bhutan, India, Japan (Ryukyu Islands), Kashmir, Laos, Myanmar, Nepal, Thailand, Vietnam]