大序野古草 da xu ye gu cao

Perennial, loosely tufted with stout scaly rhizomes. Culms stout, erect, 1.5–3 m tall, 3–10 mm in diam., many-noded, nodes appressed silky-pilose. Leaf sheaths tuberculate-hispid when young, margin densely tuberculate-ciliate; leaf blades linear-lanceolate, flat, 30–80 cm × 10–25 mm, tuberculate-hispid or glabrescent, midrib broad, white, apex finely acuminate; ligule 1–1.5 mm. Panicle narrowly oblong in outline, dense, 30–60 × 5–10 cm; central axis scaberulous; branches numerous, 5–15 cm, suberect, crowded in whorls, densely spiculate; pedicels scaberulous. Spikelets 4–5 mm, green; glumes glabrous; lower glume 3–3.8 mm, 3–5-veined, scabrid along midvein; upper glume as long as spikelet, 3–5-veined; lower floret staminate, slightly longer than lower glume; upper floret ca. 2 mm, lemma awned; awn geniculate with brown twisted column, ca. 4 mm; callus hairs ca. 1/4 length of lemma. Fl. and fr. Jul.

Mountain grasslands, hill thickets; 500–1500 m. SW Guangxi, SW Guizhou, S Yunnan [Thailand, Vietnam].

This large, robust species is similar in habit to Arundinella decem-pedalis, and grows in the same habitats, but does not occur west of Yunnan. The panicle is denser, with rather shorter branches, and the spikelets have well-developed, persistent awns.