Australian Tropical Rainforest Plants - Online edition

Cyperus bulbosus Vahl

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Inflorescence. © R.L. Barrett
Inflorescence. © R.L. Barrett
Base of plant. © R.L. Barrett
Herbarium specimen. © DERM

Vahl, M.H. (1805) Enumeratio Plantarum 2: 342. Type: Habitat ad Senegal, in Guinea ac in India Orientali. Jussieu, Thonning, Konig.

Common name

Australian Bush Onion


Slender perennial sedge with short rhizomes covered in reddish brown leaf remains. Stems strongly triquetrous, smooth and bulbous at base, dark brown to blackish, 20-40 cm tall.


Leaves as long as the culms, 1-2 mm wide; midvein prominent on lower surface of leaf.


Inflorescence much longer than the leaves; inflorescence branches with tubular sheaths; spikes to 5 cm long; involucre bracts distant from one another, leaf-like with at least 1 greatly exceeding the inflorescence. Spikelets flattened, 10-30 per spike, 10-25 mm long, 5-20 -flowered. Glumes subacute, with 3-5 nerves on either side of green keel, 3-5 mm long, ornge to red-brown.


Nut trigonous, obovoid to ellipsoid, about two-fifths as long as glume, 1.3-1.5 mm long, dark greyish to blackish with a very smooth testa.


Features not available.

Distribution and Ecology

Occurs in WA, NT, CYP, NEQ and CEQ and widespread in inland Australia. Growing in notophyll vine forest, Eucalypt woodland and Chenopod shrubland. Also in Africa, Malesia and Asia.

Natural History & Notes

Commonly as a weed of cultivation.

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