Small tree to c. 10 m high; ultimate branches ± pendulous; bark somewhat rough towards base. Shoots dark, with glaucous-white bloom in first 1-3 years, rather brittle, lacking striations below bark; buds glaucous, densely hairy. Petiole 1-2 cm long. Lamina 5-18 × 0.7-3 cm, usually linear-lanceolate, green, glaucescent or glaucous below, shining above, soon glabrous, bitter to taste, glandular-serrulate, slightly undulate; apex acuminate. Stipules 0.5-2 cm long, lanceolate. Catkins ?, mainly appearing before lvs, 3-5-(6) cm long, broad-cylindric, ± erect; rachis villous. Bracts 1-3.5 mm long, ovate or subovate, black in upper 3/4 or more, silky hairy; apex acuminate. Gland 1, 0.2-1.2 mm long, narrow-cylindric. Stamens 2, glabrous; anthers yellow.