Tree to c. 25 m high; branchlets slender, often semi-drooping. Bark smooth at first, silvery-white and papery, usually becoming dark grey and rough at least on lower trunk. Shoots glabrous, ± glandular-resinous, prominently lenticellate and appearing warty. Petiole slender, mostly 7-25 mm long. Lamina 3-6 × 1.5-5.5 cm, deltoid, ovate or rhombic-ovate, glabrous, with 5-7 pairs of veins, glandular-resinous when young, coarsely and doubly serrate; base subcordate, truncate or broadly cuneate; apex acuminate. ♂ catkins 2-9 cm long; bract 2-3 mm long, shield-like, both bract and bracteoles ciliolate. ♀ catkins 1.5-2.5 cm long, scarcely elongating at fruiting but becoming broadly cyclindric and c. 0.7 cm wide. Stigmas rose. Scales 3.5-4.5 × 4-5 mm, puberulent; lateral lobes broader and rounder than middle lobe, widespreading and often ± downward curving. Fr. 1.5-2.5 mm long; wing much > fr.