Tree to c. 60 m high, with spreading habit, suckering extensively. Bark grey, fissured. Shoots ± terete, glabrous except when very young. Buds very viscid, glabrous. Young lvs very aromatic (balsam-scented). Petioles 3.5-7 cm long, ± terete when fresh, with patent hairs and glandular-viscid. Lamina 6-23 × 5.5-20 cm, broad-ovate, hairy on veins above and beneath, green above, greenish white beneath; margins ciliate, crenate-serrate with gland-tipped teeth, without translucent border; base cordate or subcordate, sometimes rounded, with 2, sometimes inconspicuous, glands; apex cuspidate or acuminate. Catkins ♀, pendulous, 13-19 cm long at anthesis. Rachis sparsely hairy. Bracts 4-5 mm long excluding long filiform lobes, glabrous, greenish white. Cup-shaped disc 1.5-3 mm deep, almost symmetric, glabrous; margin irregular. Ovary glabrous; stigmas very large, irregularly 3-lobed. Capsule 4.5-9 mm long, broad-ovoid, containing abundant, long, white, silky hairs.