Trees to 30 m tall; bark dull gray, furrowed when older; crown broadly ovoid. Branchlets yellowish, terete, glabrous. Buds russet, ovoid, very viscid. Petiole ca. as long as or longer than leaf blade, laterally flattened, glabrous; leaf blade rhombic, rhombic-ovoid, or deltoid, 5-10 × 4-8 cm, thinly leathery, abaxially greenish, adaxially green, base cuneate or broadly cuneate, rarely truncate, margin crenate-serrate, ciliate, apex long acuminate. Flower buds outwardly curved at apex. Male catkin 5-6 cm; rachis glabrous; bracts brownish, 3-4 mm, membranous, laciniate. Male flower: stamens 15-30; anthers purplish red. Fruiting catkin 5-10 cm. Female flower: ovary ovoid, glabrous, stipitate; stigmas 2. Capsule ovoid, 5-7 × 3-4 mm, 2-valved, stipitate. Fl. Apr-May, fr. Jun. 2n = ?19*, 38*, 57.

Along rivers. Native in Xinjiang; cultivated in Fujian, Hebei, Jiangsu, Liaoning, Nei Mongol, Shaanxi, Sichuan, Yunnan [N Africa, WC Asia, Europe].