Cyperus polystachyos Rottb. APNI*
Synonyms: Pycreus polystachyos (Rottb.) P.Beauv. APNI*
Cyperus polystachyos var. polystachyos APNI*
Cyperus polystachyus APNI*
Description: Tufted 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 40 cm diam.; involucral bracts leaf-like, 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 midrib, 1.7–2.5 mm long, pale yellow to red-brown, with whitish margins. Stamens 2 or rarely 1. Style 2-fid.
Nut biconvex, narrow-obovate, about half as long as glume, 1–1.2 mm long, 0.4–0.5 mm wide, red-brown to blackish.
Distribution and occurrence: Widespread on coast north from Narooma, inland north from Kenebri area. Possibly introduced in N.S.W. but may be native in tropical Australia. Introduced on LHI.
Grows in open, often disturbed situations.
NSW subdivisions: NC, CC, SC, NWS, NWP, CWS, *LHI
Other Australian states: Qld Vic. W.A. N.T.
Text by K. L. Wilson (1993); edited Aug 2007
Taxon concept: Flora of NSW 4 (1993)
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.