Plants erect. Leaves mostly cauline; blades to 22 cm long,
1.5-7 mm wide, lax to straight, conspicuously hirsute, usually with long stiff
hairs and short soft hairs, grayish-green, margins hirsute. Panicle branches
2-11.2 cm; branch axes 0.3-0.9 mm wide. Spikelets 1.4-1.9 mm long,
1.1-1.6 mm wide, elliptic, obovate, orbicular, or suborbicular, pubescent to
nearly glabrous; lower lemmas without an evident midvein; upper lemmas
1.3-2 mm.
Paspalum setaceum var. setaceum grows in open areas and sandy
soils, often at the edges of forests, primarily on the southeastern coastal
plain of the United States, from southern New England to eastern Mexico, but
extending inland to western Virginia, Missouri, and Arkansas. It also grows
in Cuba.
Plants erect to spreading. Leaves mostly cauline; blades
2-32 cm long, 3-18 mm wide, lax to somewhat stiff, glabrous or with a few hairs
along the midrib (rarely shortly pilose), dark green to purple, margins scabrous,
ciliate. Panicle branches 2-11.9 cm; branch axes 0.6-1.2 mm wide.
Spikelets 1.7-2 mm long, 1.2-1.5 mm wide, elliptic to obovate, pubescent
or occasionally glabrous; lower lemmas with an evident midvein; upper
florets 1.7-2 mm.
Paspalum setaceum var. ciliatifolium is the most variable and widespread
of the nine varieties of P. setaceum. It usually grows in sandy soil in
open areas, including disturbed areas, of prairies and forest margins. Its range
extends from Louisiana and the eastern United States to Panama, the West Indies,
and Bermuda.
Plants mostly erect. Leaves mostly cauline; blades
to 25 cm long, 2-10.2 mm wide, lax to straight, surfaces and margins evenly
hirsute, hairs 1.5-5.5 mm, light to dark green. Panicle branches 1.9-14.3
cm; branch axes 0.5-1 mm wide. Spikelets 1.8-2.5 mm long, 1.5-2
mm wide, oval to suborbicular, glabrous or with a few hairs, light green to
green; lower lemmas usually with an evident midvein; upper florets
1.8-2.3 mm.
Paspalum setaceum var. muhlenbergii is endemic to the Flora
region, extending from southern Ontario to the Gulf coast of Texas and northern
Florida. It grows in disturbed areas and on the margins of forests. It resembles var. supinum, differing
in its erect habit and, usually, in its spikelet shape and presence of a midvein
on the lower lemma.
Plants usually spreading. Leaves mostly cauline;
bladesto 31 cm long, 2.2-19 mm wide, lax to straight, long pubescent,
hairs 1.5-4 mm, yellow-green, margins ciliate, with long stiff hairs. Panicle
branches 2.2-9.9 cm; branch axes 0.6-1.5 mm wide. Spikelets
1.7-2.1 mm long, 1.2-1.6 mm wide, elliptic to obovate (rarely suborbicular),
glabrous or pubescent; lower lemmas with or without an evident midvein;
upper florets 1.7-2.1 mm.
Paspalum setaceum var. supinum grows at the edges of forests and
in disturbed areas. Within the Flora region, its range extends from Texas,
Arkansas, and Louisiana to South Carolina, Georgia, and Florida.
Paspalum setaceum var. supinum resembles var. muhlenbergii,
differing in its spreading habit and, usually, in its spikelet shape and lack
of a midvein on the lower lemma.
Plants erect to spreading. Leaves mostly cauline; blades to
30 cm long, 2.4-6.1 mm wide, conspicuously rigid, stiff, pubescent adaxially,
glabrous or sparsely pubescent abaxially, margins sometimes ciliate. Panicle
branches 4.8-11.3 cm; branch axes 0.7-1.1 mm wide. Spikelets
2-2.6 mm long, 1.6-1.8 mm wide, obovate to ovate, pubescent, sometimes sparsely
so; lower lemmas with or without an evident midvein; upper florets
2-2.4 mm.
Paspalum setaceum var. rigidifolium grows on hammocks, sand barrens,
high pinelands, and flatwoods of Georgia, Florida, and Cuba.
Plants erect. Leaves conspicuously basal; blades to 15
cm long, 3-10 mm wide, recurved, hirsute, usually with long stiff hairs and
short soft hairs, grayish-green, margins ciliate, with long stiff hairs. Panicle
branches 2-11.2 cm; branch axes 0.3-0.9 mm wide. Spikelets
1.4-1.9 mm long, 1.1-1.6 mm wide, elliptic, obovate, orbicular, or suborbicular,
short pubescent to nearly glabrous, often purple-spotted; lower lemmas
without an evident midvein; upper lemmas 1.3-2 mm.
Paspalum setaceum var. villosissimum grows in sandy fields and
flatwoods of Florida and Cuba. It resembles var. longepedunculatum,
differing in its pubescent leaves, more robust habit, and more developed rhizomes.
Plants erect to spreading. Leaves mostly cauline;
blades to 30 cm long, 3.3-13.5 mm wide, lax to somewhat stiff, glabrous
or with a few hairs along the midrib, sometimes pubescent, yellow-green to dark
green, margins scabrous, ciliate. Panicle branches 4-12 cm; branch
axes 0.6-1.1 mm wide. Spikelets 1.7-2.4 mm long, 1.5-2.1 mm wide,
obovate to suborbicular, pubescent or occasionally glabrous; lower lemmas
without an evident midvein; upper florets 1.7-2.1 mm.
Paspalum setaceum var. stramineum grows at the edges of forests
and in disturbed areas with sandy soil. Its range extends from the central plains
and eastern United States to Mexico, Bermuda, and the West Indies.