Cyperus vaginatus

Tussock-forming perennial, occasionally proliferating, with short, thick rhizome. Culms terete, rigid, smooth, to 100 cm high, to c. 3 mm diam. Leaves reduced to sheaths except in juvenile plants. Inflorescence simple or compound, with 4–12 primary branches to 6 cm long but often less, or sometimes head-like; digitate clusters to 2 cm diam.; involucral bracts mostly 5–8 exceeding inflorescence, with apex acute but not pungent, rather rigid. Spikelets flattened, 4–15 per cluster, 5–18 mm long, 2–2.8 mm wide in side view, 8–40-flowered; rachilla not winged, persistent; glumes short-mucronate, with 3-nerved keel, red-brown to straw-coloured, 2–2.5 mm long; stamens 3. Nut trigonous, obovoid to ellipsoid, grey-brown, scarcely one-half as long as glume, 0.6–0.8 mm long, c. 0.5 mm diam. Flowers spring–summer.