Plants perennial; cespitose, stoloniferous. Culms 100-200 cm, decumbent,
rooting at the lower nodes; internodes glabrous; nodes 4-10, densely
pilose. Sheaths chartaceous to cartilaginous, lower sheaths with papillose-based
hairs, upper sheaths glabrous; collars hairy; ligules 0.6-1.2 mm;
blades 6-28 cm long, 6-18 mm wide, linear, flat, straight, ascending or
drooping, glabrous adaxially. Panicles 8-20 cm long, 41-90 mm wide, open;
rachises sparsely pilose to hirsute; branches (5)10-15(18), 2-6
cm long, 0.4-0.6 mm wide, pubescent to setose, not winged, spikelets in unequally
pedicellate pairs; pedicels 0.5-1 mm, pubescent, apices glabrous. Spikelets
3.2-3.9 mm long, 1.1-1.3 mm wide, lanceolate to ovate. Lower glumes present
as a membranous extension of the calluses; upper glumes equaling the lower
lemmas, hairy, lanceolate to ovate, 5-veined, acute, unawned; lower lemmas
3-3.5 mm long, 1.1-1.3 mm wide, lanceolate to ovate, glabrous or sparsely pubescent,
5-veined, acute, unawned; lower paleas fully developed or absent; anthers
absent or 3; upper lemmas 2.2-2.6 mm, indurate, elliptic, rounded, mucronate,
mucros less than 0.2 mm; upper paleas 2-2.5 mm, indurate. 2n = 36.
Eriochloa polystachya is native to the West Indies, Costa Rica, Honduras,
and South America. It was introduced into the United States as a forage crop and
is now established at some locations in Florida and Texas.