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.
Culms glabrous, when submersed elongate and little branched, when terrestrial tufted from the base; sheaths loose, papillose-hispid to glabrous; lf-blades tapering at both ends, thin, (5-)8-12(-20) cm, often 1 cm wide or more; racemes numerous (usually 20-50), crowded, spreading or ascending, 2-4 cm; rachis 0.8-2 mm wide, its acuminate tip surpassing the uppermost spikelet by 1-3 mm; spikelets solitary (not paired), elliptic, acute, 1.1-1.5 mm; glume and sterile lemma 2-veined near the margin, the glume finely glandular-villosulous; 2n=20. Shallow water, swamps, and muddy shores; widespread in s. U.S., n. on the coastal plain to se. Va. and in the Mississippi Valley to w. Ky., s. Ind., c. Ill., and c. Mo. (P. mucronatum; P. repens, misapplied)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.