西南野古草 xi nan ye gu cao

Arundinella chenii Keng; A. villosa Arnott ex Steudel var. himalaica J. D. Hooker.

Perennial, tufted with a short knotty rhizome, base clothed with old papery sheaths. Culms erect or ascending, herbaceous, (18–)30–60(–90) cm tall, 1–3 mm in diam., internodes glabrous, 1–2-noded, nodes purple, glabrous or puberulent. Leaf sheaths shorter than internodes, densely hirsute; leaf blades mainly basal, linear-lanceolate, 2–20 cm × 2–12 mm, densely villous, apex acute; ligule 0.2–0.5 mm. Panicle contracted, oblong or narrowly pyramidal in outline, 3–12 cm; central axis densely pubescent; branches 1–2(–3) cm, suberect or ascending, inserted singly, spaced below, crowded above, densely spiculate; pedicels short, densely pubescent. Spikelets 5–7 mm, gray-green tinged purplish; glumes 5-veined, setose on veins, apex caudate; lower glume 3.5–5 mm; upper glume 4.5–6 mm; lower floret staminate, ± equaling lower glume; upper floret 2.5–3.5 mm, lemma apex emarginate, awned; awn geniculate with brown twisted column, 2–5 mm; callus hairs 2/5 length of lemma. Fl. and fr. Oct–Nov.

Common on mountainsides, open forests, meadows; 1800–3200 m. W Guizhou, SW and W Sichuan, SE Xizang, Yunnan [Bhutan, NE India, N Myanmar, Nepal].

This slender species is recognized by its tufts of hairy leaves; compact panicle with short, broad branches of densely packed, large spikelets; setose, caudate glumes; and clearly visible, geniculate awns.