Plants hermaphroditic, caespitose or rhizomatous, annual (ours) or perennial. Culms erect, glabrous or hairy; internodes solid,
terete. Leaves cauline; sheaths terete, margins open; auricles absent; ligules a line of hairs; blades flat or involute, not
pungent. Panicles open (exserted or included in sheath); primary branches spreading, terminating in a spikelet.
Cleistogamous spikelets in axillary panicles of sheaths. Spikelets solitary, laterally compressed, awned, pedicellate; pedicels
without glands; disarticulation above glumes; florets 2 - 5, callus hairy; reduced florets at apex; glumes 1-veined,
unequal, second glume shorter or equal to first floret, glabrous; lemma 3-veined, membranous, lobed, awned (lateral
veins extending to mucros), glabrous (except pilose at base), veins hairy; paleas 2-veined, awnless, pilose on upper half.
Stamens 3; anthers reddish purple. Caryopses dorsiventrically compressed; pericarp striate, reddish. Base chromosome number x=10.
A genus of two species native to North and Central America. These species are adapted to sandy soils.