Betula potaninii Batalin var. trichogemma Hu ex P. C. Li, Acta Phytotax. Sin. 17(1): 91. 1979.

Shrubs or trees to 4 m tall; bark gray-brown. Branchlets brown, densely grayish tomentose. Bud scales densely grayish tomentose. Petiole ca. 2 mm, densely villous; leaf blade ovate-elliptic or elliptic, 1.5-3 × 0.8-1.5 cm, abaxially yellow-brown tomentose along veins, adaxially pubescent along midvein, base rounded or broadly cuneate, margin obtusely simply serrate, rarely mucronate serrate, apex acute or obtuse; lateral veins 11-14 on each side of midvein, raised abaxially, deeply impressed adaxially. Female inflorescence oblong-cylindric, 1.2-1.6 cm × 3-4 mm; bracts ca. 4 mm, densely pubescent and ciliolate, 3-lobed, middle lobe ovate-oblong, lateral lobes obovate, ca. 2/3 as long as middle lobe. Nutlet suborbicular, 2-2.5 × 1.8-2.2 mm, sparsely pubescent, with very narrow wings. Fl. Jun, fr. Jul-Aug.

A. K. Skvortsov indicates that this species is very similar to Betula calcicola and B. jiulungensis, and further studies may show that it is conspecific with one of them.

* Thickets on cliffs; 2400-3100 m. Sichuan (Emei Shan)