Cyperus polystachyos
Rottb. Bunchy Flat-sedgeTufted annual or perennial with short rhizome. Culms trigonous to triquetrous, smooth, 10–60 cm high, 1–2.5 mm diam. Leaves not septate-nodulose, shorter than culms, 2–3 mm wide. Inflorescence simple or subcompound with 3–8 primary branches to 6 cm long, or head-like; clusters subdigitate, broad-obovoid to hemispherical, to 4 cm diam.; involucral bracts leaflike, 2–4 exceeding inflorescence. Spikelets flattened, numerous per cluster, 5–25 mm long, c. 1.5 mm wide in side view, 10–50-flowered; rachilla narrowly winged, persistent; glumes obtuse, short-mucronate, with 3-nerved keel, pale yellow to red-brown, with whitish margins, 1.7–2.5 mm long; stamens 2 or rarely 1. Nut biconvex, narrow-obovate, red-brown to blackish, c. one-half as long as glume, 1–1.2 mm long, 0.4–0.5 mm wide. Flowers spring–summer.
GipP, HSF. All mainland States (including Lord Howe Is.) except SA. Pantropical. Known only from the Providence Ponds area (between Stratford and Bairnsdale) where probably an introduction.
Wilson, K.L. (1994). Cyperaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 238–356. Inkata Press, Melbourne.
