Tussock-forming perennial. Culms 60–110 cm high, 2–3 mm diam. Leaf-blades flat to inrolled, erect to spreading, smooth to finely scabrous, as long as or longer than culm, shorter than inflorescence; ligules chartaceous, to 8 mm long; sheaths pink-purplish and dull above to black and very shining at base. Inflorescence very narrow, erect, 20–35 cm long, with 2–3 nodes, spikelet clusters very dense. Spikelets 1-flowered; glumes 3 or 4, similar in size, brown, minutely scabrous to smooth, with acute to acuminate apex; stamens 3; anthers c. 1.8 mm long excluding appendage 0.4–0.5 mm long. Nut ± linear to very narrow-ovoid, trigonous, granulate, glistening, 5–6 mm long, 1.0–1.5 mm diam., straw-coloured to very dark brown. Flowers spring–summer.