Fuirena umbellata Rottb.

Perennial with short thick rhizome. Stems tufted, erect, slender to rather stout, acutely 4-5-angular, pubescent in the inflorescence or very rarely through-out, 30-110 cm by up to 8 mm at the base, the lowest internode not rarely bulbously thickened. Leaves much shorter than the stems, rather rigid, flat, acute, glabrous or ciliate at the base, very rarely pubescent, with 5 prominent nerves, (5-)8-15(-25) mm wide, the lower ones very short; sheaths shorter than the internodes, usually glabrous. Inflorescence usually with a terminal partial inflorescence and several axillary ones, the latter single or binate, on pubescent peduncles. Lower bracts similar to the leaves, as long as or slightly overtopping the inflorescence, obliquely erect to patent, sheathing at the base; upper ones much shorter, not or hardly sheathing. Spikelets in very dense clusters, ovoid to oblong-ovoid, acute, finally more or less squarrose, brownish or greyish to blackish green, 4-10 by 2½-3 mm. Glumes membranous, ovate or obovate, rounded at the apex, short-hairy, pilose at the apex, 2-2½ by 1¼-1½ mm, somewhat below the apex with a recurved, often pilose, ¾-1⅓ mm long awn. Perianth usually uniseriate; bristles usually absent, very rarely present, but always much shorter than the nut; scales about as long as the nut, subsessile (with a very short curved claw), obovate, narrowed at the base, truncate at the somewhat thickened top, the midnerve usually excurrent into a short curled mucro, minutely ciliolate at the apex, 3-nerved, brown. Stamens (2-)3; anthers linear-oblong, ½-¾ mm long. Nut elliptic to obovate, triquetrous, narrowed into a stipe and beak, smooth, shining stramineous to fuscous, 1-1¼ by 0.6-0.7 mm.

Common in open wet locations, sometimes in secondary forest; at elevations up to 1,800 metres. Areas of permanent shallow water, swamps, pools, ditches, marshy lake shores, even in brackish sites.

Can be grown by seedlings.