Perennial with short, stout rhizome. Culms rigid, terete, transversely septate (not obvious when fresh), nodeless, striate, smooth or scabrous, 90–200 cm high, 4–10 mm diam. Leaves usually basal (sometimes a short leaf developed on the upper portion of the culm); blade culm-like, equalling or exceeding culm, to 10 mm diam.; sheath straw-coloured, dull. Inflorescence oblong in outline, loose, drooping, 15–45 cm long, to 10 cm diam.; lowest involucral bract shorter than inflorescence. Spikelets numerous, 2–5-flowered, 3.5–5 mm long; glumes 4–7, acute, often mucronate, red-brown, glabrous; fertile glumes 3.5–5 mm long. Nut ellipsoid to ovoid, strongly and irregularly wrinkled, ± smooth at apex and base and on the 3 angles, hispid or papillose at apex, ± dull, pale to dark red-brown, 1.8–2.8 mm long, 1.2–1.4 mm diam. Flowers spring–summer.