Plants perennial; rhizomatous. Culms 80-210 cm, erect; nodes
glabrous or pubescent. Sheaths glabrous or pubescent; ligules
1.2-3.3 mm; blades to 52 cm long, 3-18 mm wide, flat, glabrous or pubescent,
usually densely pubescent behind the ligules. Panicles terminal, with 1-6
racemosely arranged branches; branches 3-17.9 cm, divergent to erect, terminating
in a spikelet; branch axes 0.3-1.8 mm wide, glabrous, the margins scabrous.
Spikelets 2.9-4.1 mm long, 1.9-3.1 mm wide, paired, imbricate, appressed
to the branch axes, elliptic to suborbicular to orbicular, glabrous, stramineous.
Lower glumes absent; upper glumes glabrous, 5-veined, margins entire;
lower lemmas glabrous, lacking ribs over the veins, 3-veined, margins entire;
upper florets golden brown. Caryopses 2.8 mm, amber. 2n =
120, 140, ca. 160-170.
Paspalum floridanum grows along the edges of forests, flatwoods, and pinewoods
and in open areas. It is a frequent component of dry-mesic soils in longleaf pine-oak-grass
ecosystems, and is restricted to the eastern United States.
Stout, erect, 1-2 m; lvs elongate, 5-10 mm wide, pubescent at least at base; uppermost sheath bladeless or nearly so; peduncle 2-3 dm; racemes 2-5, 6-10 cm, sparsely silky at base, the narrow axis scaberulous or rarely long-pilose, somewhat flexuous; spikelets in pairs or apparently solitary, one sometimes represented by a sterile pedicel, round-obovate, varying to elliptic or rarely ovate, blunt, glabrous, 3.8-4.3 mm, two-thirds to almost as wide; glume and sterile lemma 5- veined, the outer veins approximate near the margin; fertile lemma pale brown, shining, minutely rugulose; 2n=120, 160. Moist, usually sandy soil on the coastal plain from s. N.J. to Fla. and Tex., n. in the interior to s. Mo. and e. Kans. (P. glabratum, a form with glabrous lower sheaths)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.