Australian Tropical Rainforest Plants - Online edition

Cyperus bulbosus Vahl


Grass
Click/tap on images to enlarge
Inflorescence. © R.L. Barrett
Inflorescence. © R.L. Barrett
Base of plant. © R.L. Barrett
Herbarium specimen. © DERM
Family

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

Stem

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

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

Flowers

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.

Fruit

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.

Seedlings

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.

RFK Code
4197
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