Cyperus lucidus

Robust tussock-forming perennial with short thick rhizome. Culms 30–150 cm high, trigonous, smooth, to 10 mm diam. Leaves strongly septate-nodulose, often longer than culms, 5–40 mm wide. Inflorescence compound with 6–10 primary branches to 20 cm long; spikes ovoid to cylindric, 1–3 cm long and diam.; involucral bracts leaf-like, 5–10 much exceeding inflorescence, to 150 cm long. Spikelets terete to flattened, numerous per spike, 4–20 mm long, 1–2.5 mm wide in side view, 4–10-flowered; rachilla broadly winged; spikelet falling as unit; glumes acute, with sides 2–4-nerved, red-brown, 4–6.5 mm long; stamens 3; style 3-fid. Nut trigonous, very narrow-ellipsoid, dark grey-brown to blackish, c. two-thirds as long as glume, 2.5–3 mm long, c. 0.7 mm diam. Flowers spring–summer.