Plants perennial; cespitose, with a knotty base composed
of very short (less than 1 cm) rhizomes. Culms 50-220 cm, erect; nodes
glabrous or pubescent. Sheaths glabrous or pubescent; ligules
1-4(7.7) mm; blades 12-60 cm long, 2-12 mm wide, flat, mostly glabrous,
a few long hairs near the base of the adaxial surface. Panicles terminal,
with (4)10-30 racemosely arranged branches; branches 1.2-11.5 cm, divergent;
branch axes 0.5-1.1 mm wide, winged, glabrous, margins scabrous, terminating
in a spikelet. Spikelets 1.8-2.8 mm long, 1.1-1.5 mm wide, paired, appressed
to the branch axes, elliptic to slightly obovate, stramineous (rarely purple).
Lower glumes absent; upper glumes and lower lemmas 3-veined,
margins pilose; upper florets stramineous. Caryopses 1.2-1.7 mm,
white. 2n = 40.
Paspalum urvillei has been introduced to the United States from South
America. In the Flora region it grows in disturbed, moist to wet areas,
primarily in the southeastern United States.
Densely cespitose, stout, erect, to 2 m; upper blades and sheaths glabrous, lower sheaths and base of the lower blades hirsute; panicle much surpassing the upper lf, dense, the numerous (8-30) racemes erect or appressed, 5-10 cm; spikelets elliptic, acute, 2.2-2.8 mm; glume white-villous; sterile lemma nearly glabrous; fertile lemma shorter and blunt; 2n=40, 60. Waste ground; native of trop. Amer., now widespread from s. U.S. (n. to Va.) s. to Argentina.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.