Medium-sized trees. Buds greyish-brown; branchlets with small, light coloured lenticels. Leaves opposite or in whorls of three, c. 20 cm long; leaflets 3-7, 4-7 cm long, 2-3 cm broad, ovate, long-acuminate, coarsely serrate, green and glabrous on both sides, sessile. Inflorescence decussate on shoots of the previous year appearing before the leaves; flowers bisexual; pedicels 5-8 mm long. Bracts 1-3 mm long, often divided, covered with brown hairs. Calyx and corolla lacking. Anthers purple, with short filament (c. 1 mm), greatly exceeded by pistil. Stigma hardly 2-lobed, pointed at apex. Samarae oblanceolate, twisted when ripe, c. 3 cm long, rachis 3-6 cm long.