Herb, perennial, dioecious, rhizomatous, forming extensive diffuse patches. Rhizome elongated, stout, to 30 cm (or more) long, 3–5 mm diam., densely tomentose with white hairs; cluster roots present. Cataphylls similar to sheaths but shorter. Scales scarious, broad-deltoid, 4–7 mm long, glabrous. Cataphylls several, short (5–10 mm long), broad-deltoid, pale, scarious. Culms at intervals of 1–3 cm on the rhizome, erect, stout, 7– 40 cm long, 2–3 mm diam., unbranched, glabrous, smooth when fresh but often irregularly striate when dry. Sheaths 2–7, appressed or slightly lax, 5–20 mm long, rigid, truncate, with a filiform mucro 1 mm long, scarious, pale, glabrous except for the finely ciliate ligule; ligule a narrow ridge with dense white hairs, the lamina flanked by very short auricles. Spathes similar to sheaths. Spikelets 1–7 on the culm, sessile or on short pedicels 1–5 (–10) mm long: males ovoid, 4–7 mm long, with c. 12–25 flowers; females narrow-ovoid, 1–3-flowered; glumes lanceolate, acuminate, c. 3.5 mm long, red-brown with narrow membranous and shortly fimbriate margin. Male flowers: outer tepals narrow-lanceolate, acuminate, c. 3 mm long, keeled; inner tepals shorter, membranous, subacute. Female flowers shortly petiolate; bracts 2, subequal, 3–4 mm long, keeled; tepals similar to males; styles 3, stout, strongly recurved. Fruit a nut (Meney et al. 1999) but mature fruit and seed not seen.
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