Plants annual; aquatic, floating or rhizomatous. Culms 4-55 cm, erect; nodes pubescent. Sheaths glabrous or pubescent; ligules 1-4 mm; blades 10-40 cm long, 8-22 mm wide, flat, glabrous or sparsely pubescent. Panicles terminal, with (7)20-70 racemosely arranged branches; branches 1.2-9.5 cm, diverging to spreading, occasionally arcuate, disarticulating at maturity; branch axes 0.7-1.5 mm wide, broadly winged, glabrous, margins scabrous, extending beyond the distal spikelet. Spikelets 1.1-1.9 mm long, 0.5-0.8 mm wide, solitary, appressed to the branch axes, elliptic, pubescent, white. Lower glumes absent; upper glumes and lower lemmas veinless; upper florets white. Caryopses 0.8-0.9 mm, translucent, white. 2n = 20.

Paspalum repens is a native species that grows along the edges of lakes, streams, and roadside ditches in the southeastern United States. Its range extends through tropical America to Peru, Bolivia, and Argentina.

From Flora of Indiana (1940) by Charles C. Deam

Infrequent to local in the state and restricted to the muddy banks of ponds, sloughs, and streams. The oldest specimen seen was one collected in 1836 near New Albany by Dr. Clapp.