Trees, to 25 m tall, d.b.h. to 80 cm, deciduous. Bark dark gray, longitudinally fissured, scabrous, exfoliating in irregular flakes. Branchlets brown to dark brown, glabrous or pubescent when young, soon glabrescent, unwinged and without a corky layer, with scattered lenticels. Winter buds dark purplish brown, ovoid; bud scales finely and inconspicuously puberulent, margin entire or inconspicuously short-ciliate. Petiole 2-6 mm, pubescent; leaf blade elliptic to oblong-elliptic, 5-11 × 3-4.5 cm, abaxially densely pubescent with conspicuous tufts in vein axils, adaxially smooth and glabrous or with scattered hairs, base obtuse to obliquely truncate, margin doubly serrate, apex caudate; secondary veins 11-20 on each side of midvein, tufted pubescent in axils. Inflorescences fascicled cymes on second year branchlets. Perianth campanulate, 5- or 6-lobed. Samaras tan, obovate to obovate-orbicular, 1-1.5 × 0.8-1 cm, glabrous except for pubescence on stigmatic surface in notch; stalk almost as long as or slightly shorter than perianth, pubescent; perianth persistent. Seed at center of samara. Fl. and fr. Feb-Mar.

* Forests in mountains; 800-2500 m. C Taiwan.