Description from Flora of China
Trees to 20 m tall; bark grayish white, smooth. Old branches gray; branchlets dull brown, at first pilose, glabrescent. Buds reddish brown, ovoid or conical; scales white downy, viscid. Leaves of short branchlets with petiole compressed, 3.5-6.5 cm; leaf blade ovate-orbicular or deltoid-orbicular, 5.5-8.5 × 5-8 cm, larger on sprouts, abaxially grayish green, adaxially green, both surfaces white downy when leaves unfold, base shallowly to deeply cordate or truncate, margin sinuously obtusely serrate, apex shortly acuminate or obtuse. Leaves of sprouts with petiole shorter; leaf blade ovate-orbicular, larger, base cuneate or subcordate. Female catkin 4-7 cm, ca. 10 cm in fruit; rachis pilose. Female flower: ovary long ovoid, glabrous; style short or subsessile; stigma 2-parted. Capsule long ovoid, 2-valved.
Mountain slopes; circa 2800 m. Gansu, Guizhou, Shaanxi, Sichuan, Xizang, Yunnan [Bhutan].