Common name: Nutgrass
Cyperus rotundus L. APNI*
Description: Rhizomatous perennial with slender rhizomes forming ovoid to ellipsoid tubers 5–10 mm diam., woody, with deciduous grey-brown fibrous coat.
Culms triquetrous, smooth, 15–30 (occasionally to 60) cm high, 1–2 mm diam.
Leaves not septate-nodulose, shorter than culms, 2–6 mm wide. Inflorescence mostly simple with 3–9 primary branches to 10 cm long; spikes short, ovoid, to 2.5 cm long, to 3 cm diam.; involucral bracts leaf-like, 2–4 not or slightly exceeding inflorescence. Spikelets flattened, 3–10 per spike, 10–40-flowered, to 25 mm long, c. 2 mm wide in side view; rachilla broadly winged, persistent. Glumes obtuse, with sides several-nerved, 3–3.5 mm long. Stamens 3. Style 3-fid.
Nut rarely maturing, trigonous, narrowly obovoid to ellipsoid, less than half as long as glume, c. 1.5 mm long, c. 0.5 mm diam., dark grey-brown.
Distribution and occurrence: Weed in disturbed situations, mostly around habitation but occasionally infesting crops; widespread but scattered. Native of Afr. & Asia.
NSW subdivisions: *NC, *CC, *SC, *ST, *NWS, *CWS, *SWS, *NWP, *LHI
Other Australian states: *Qld *Vic. *W.A. *S.A. *N.T.
Text by K. L. Wilson
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.