Cyperus involucratus Rottb.

Rottboell, C.F. (1772) Descriptiones Plantarum Rariorum: 22.

Umbrella plant

Perennial sedge with short rhizome. Stems tufted, rigid, subterete to trigonous below inflorescence. Usually flowers and fruits when ca. 1-2 m tall.

Leaf blades grass-like, 20-30 x 0.4-1.5 cm, margins finely toothed and quite capable of cutting fingers, midrib similarly toothed.

Inflorescence terminal, produced on a long peduncle which ends in a series of l12-22 leafy bracts which are much longer than the inflorescences. Inflorescence a panicle of spikes. Spikes up to 2 x 2 cm; spikelets compressed, 5-10 x 1.8-2 mm, 20-40 -flowered; rachilla straight; glumes 1.8-2 mm long. Anthers ca. 1 mm long, filaments ca. 0.25 mm long. Style ca. 1 mm long and then divided into three branches each ca. 1.5 mm long.

Nut yellowish brown, ellipsoid, trigonous, apiculate and nearly length of the glume.

Features not available.

An introduced species with a pantropic distribution, now naturalised in WA, NT, CYP, NEQ, CEQ and southwards in Australia. Altitudinal range in NEQ from near sea level to 520 m. Grows in various types of vegetation including rain forest, but usually found in swampy situations on the edge of waterways.