Perennial, tufted, rhizomatous; rhizomes spreading. Culms erect, 40–150 cm tall, 1.5–4 mm in diam., 2–6-noded, scabrid below panicle. Leaf sheaths smooth or scabrid; leaf blades flat or weakly inrolled, 10–30 cm, 2–5(–7) mm wide, adaxial surface and margins scabrid, abaxial surface smooth; ligule 4–10 mm, obtuse or lacerate. Panicle oblong-lanceolate, rather lax, 10–30 × 2–5 cm, primary branches distinct, nodding; branches in dense whorls, scabrid. Spikelets 5–9 mm, yellowish green or purple; glumes linear-lanceolate, unequal, upper glume 2/3–3/4 length of lower glume, keel scabrid, apex acuminate-subulate; callus hairs 2–3 times length of lemma; lemma about 1/2 as long as glumes, 3–4 mm, 3-veined, apex entire or 2-denticulate; awn arising just below lemma apex, 1–3 mm, scarcely projecting from glumes, straight; palea 1/2–2/3 as long as lemma. Stamens 3; anthers 1–2 mm; rachilla not extended. Fl. and fr. Jul–Sep.