Annual; decumbent-spreading, rooting at lower nodes; culms slender, glabrous, freely branching. Sheaths much shorter than internodes, papillose-hispid and ciliate, prominently veined; blades lanceolate, 2-5 cm long, 5-10 (15) mm wide, rounded to subcordate at base, strigose to papillose-hispid especially below, the margins white and scabrid. Panicles diffuse, 5-10 cm long, nearly as wide, the branches slender, glandular-spotted; spikelets subglobose,1.5-2 mm long; glumes equal, slightly shorter than spikelet, glabrous to sparsely pubescent above middle; florets 2, one staminate and similar in size and texture to the second glume, the other perfect. Fruits ca 1.3 mm long, white, plano-convex, densely pubescent. Croat 13242. Infrequent, in marshes and floating masses of vegetation along the shore. Probably flowers throughout the year.