西藏狼尾草 xi zang lang wei cao

Perennial with extensive branching rhizomes clothed in cataphylls. Culms erect, 25–150 cm tall. Leaf sheaths usually pubescent; leaf blades linear, 10–45 × 0.4–1.3 cm, pubescent to villous or occasionally glabrous; ligule 1–2 mm. Inflorescence linear, 5–15 × 1.5–2.5 cm; axis loosely pubescent, with shallow angular ribs below the cupular involucre-scars; involucre enclosing 2–4 shortly pedicelled spikelets; bristles greenish, softly plumose, rarely almost glabrous, branched (often several times) above the base. Spikelets ovate-lanceolate, 4–5.5 mm; lower glume 1/3–2/5 as long as spikelet, 3-veined, subacute to rotund, rarely apiculate; upper glume 1/2 as long as spikelet, obtuse to apiculate; lower floret staminate, lemma as long as spikelet, acuminate; upper lemma slightly shorter than lower, acute; anthers without hairs at tip. Fl. and fr. Aug–Oct.

Dry mountain slopes; above 1500 m. W Xizang [Afghanistan, NW India, Kashmir, Nepal, Pakistan].

This is a distinctive species on account of its long, scaly rhizomes and branched bristles in the inflorescence.