Actinoscirpus grossus (L.F.) Goetgh. & D.A.Simpson

Plants stoloniferous. Culms scattered, 1-2 m tall, 1-1.2 cm thick, acutely 3-angled, smooth, clothed at base with 1 or 2 spongy leaf sheaths which disintegrate into reticulate fibers. Leaves basal only (not cauline), shorter than culm; sheaths spongy; leaf blade 7-12 mm wide, margin scabrous. Involucral bracts 3 or 4, leaflike, basal 1-3 longer than inflorescence, margin apically scabrous. Inflorescence a terminal compound anthela, with over 10 rays and many spikelets; rays to 5 cm, scabrous. Spikelets solitary, rust-colored to dark brown, sessile or pedunculate, ovoid to ellipsoid, 4-5 × 2.5-3 mm, densely many flowered. Glumes elliptic to broadly ovate, ca. 2.5 mm, membranous, margin apically ciliolate, apex obtuse with a green costa excurrent into a mucro. Perianth bristles 6, longer than nutlet, retrorsely scabrous. Stamens 3; anthers linear; connective apex black, deltoid, very short. Style ± long; stigmas 3. Nutlet pale brownish yellow, obovoid to subellipsoid, ca. 1.5 mm, compressed 3-sided, apex beaked. Fl. and fr. Jul-Oct. 2n = ca. 88.

A tropical plant. Common in open swamps at low altitudes and widely distributed in the Philippines. In southern China it grows in paddy fields and moist places between 100-900 m above sea level. In Yunnan.

CAUTION: The roots are poisonous unless properly processed. The roots are edible after proper processing and then cooked. They are crushed and burnt then ground into flour. They are dried before being ground into flour. (NB Drying often removes a poison.)