西藏三毛草 xi zang san mao cao

Trisetum tibeticum P. C. Kuo & Z. L. Wu, Fl. Xizang. 5: 188. 1987.

Plant 3–12 cm. Culms woolly, leaf blades and sheaths tomentose. Panicle ovate to oblong, dense, 1.7–3 cm, usually purplish or brownish. Spikelets with 2 florets; lower glume 4–7 mm, keel sometimes hispid, upper glume 5–7 mm; lowest lemma 4.8–5 mm, densely pubescent, apex 2-denticulate-aristulate; awn 5–5.6 mm, weakly geniculate, twisted below. Fl. and fr. Jun–Sep.

* Among boulders, glacial moraines; 4800–5500 m. Xizang.

Plants from very high altitudes in Xizang are distinguished by their low stature, extremely hairy leaves and culms, and especially by their pubescent lemmas. They grade into subsp. mongolicum through forms with shorter hairs on the lemma back and less densely hairy leaves and culms.