6. Larix potaninii Batalin, Trudy Imp. S.-Petersburgsk. Bot. Sada. 13: 385. 1894.
红杉 hong shan
Trees to 50 m tall; trunk to 1 m d.b.h.; bark gray or gray-brown, rough, longitudinally fissured; crown conical; long branchlets reddish brown or purplish brown, rarely initially yellowish brown, finally dark gray; short branchlets 3-8 mm in diam., glabrous or densely yellowish brown hairy at apex; winter buds brown or dark brown, glossy, ovoid. Leaves 1.2-3.5 cm × 1-1.5 mm, keeled on both sides. Seed cones reddish or purplish, maturing purplish brown or light gray-brown, cylindric or ovoid-cylindric, 2.5-7.5 × 1.5-3.5 cm. Seed scales 35-90, slightly convex, 0.8-1.6 × 0.8-1.1 cm, as wide as or wider than long, ± strigose to pubescent and tuberculate abaxially, apex truncate or obtuse-rounded. Bracts often exserted, purplish brown, oblong-lanceolate, straight, apex acute or acuminate. Seeds light brown with irregular purplish spots, obliquely obovate, obliquely obovoid, 7-10 mm including wing. Pollination Apr-May, seed maturity Oct.
* Mountains, river basins; 2500-4300(-4600) m. S Gansu, S Shaanxi, Sichuan, SE Xizang, N Yunnan
The timber is used for construction, pit props, railway sleepers, and making furniture, and the bark yields tannins. The species is also used for afforestation.