Cyperus bifax C.B.Clarke

Bull. Misc. Inform, add. ser. 8: 13 (1908) APNI

Taxonomic status:Accepted

Occurrence status:Present

Establishment means:Native

Threat status:Victoria: vulnerable (v)

Rhizomatous perennial with slender rhizomes producing woody, ovoid tubers c. 0.5–1 cm diam., with a grey-brown fibrous coat persisting for two years. Culms trigonous, smooth, to 90 cm high, 2–4 mm diam. Leaves not septate-nodulose, mostly from one-half to three-quarters as long as culm, to 4 mm wide. Inflorescence simple or compound, symmetrical (not thrown to one side), with 2–9 primary branches to 12 cm long; spikes ovoid, to 4 cm long, to 3 cm diam.; involucral bracts leaf-like, 1 or 2 much exceeding the inflorescence. Spikelets flattened, 5–10 per spike, 10–40 mm long, 2.5–3 mm wide in side view, 10–24-flowered; rachilla winged, persistent; glumes acute, with sides 1–3-nerved, very pale red-brown to orange-brown or red-brown, rarely very dark, 3–4 mm long; stamens 3; style 3-fid. Nut trigonous, broad-obovoid, greyish, c. 1.5 times as broad as long, c. 1.2 mm long, c. 0.8 mm diam. Flowers spring–summer.

MuF, MuM, VRiv. Also WA, NT, Qld, NSW. Malesia, Asia, Africa, ?South America. Known in Victoria only from the Kerang and Lalbert areas, but widespread in inland Australia, especially on floodplains on heavy clay soils. Occasionally a weed of cultivation, especially in irrigation areas.

Cyperus bifax withstands heavy grazing, and its system of rhizomes forms a useful soil-binding agent.

Source: Wilson, K.L. (1994). Cyperaceae. In: Walsh, N.G.; Entwisle, T.J. (eds), Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons. Inkata Press, Melbourne.
Updated by: Val Stajsic, 2019-02-13
Hero image
Distribution map
life Life
kingdom Plantae
phylum Tracheophyta
superorder Lilianae
order Poales
family Cyperaceae
genus Cyperus
Higher taxa


Source: AVH (2014). Australia's Virtual Herbarium, Council of Heads of Australasian Herbaria, <>. Find Cyperus bifax in AVH ; Victorian Biodiversity Atlas, © The State of Victoria, Department of Environment and Primary Industries (published Dec. 2014) Find Cyperus bifax in Victorian Biodiversity Atlas
  Bioregion Occurrence status Establishment means
Murray Mallee present native
Victorian Riverina present native
Murray Fans present native

State distribution

Distribution map
Western Australia
Northern Territory
South Australia
New South Wales
Australian Capital Territory