Plants perennial; cespitose or not, with or without rhizomes. Culms 8-80 cm, erect or decumbent, solitary or in small to large groups. Leaves evenly distributed; sheaths mostly glabrous, sometimes with hairs distally; ligules 0.3-0.5 mm, membranous, ciliate; blades 2-30 cm long (1.4) 2.5-7 mm wide, at least some over 2.5 mm wide, flat or folded when dry, usually smooth abaxially and scabrous adaxially, occasionally pubescent, bases usually with papillose-based hairs on the margins. Panicles 13-30 cm, secund, with (12) 30-80 reflexed branches; branches (5) 10-30 (40) mm, deciduous, with (1) 2-7 (15) spikelets, axes terminating 3-5 mm beyond the base of the terminal spikelets, apices entire; disarticulation at the base of the branches. Spikelets appressed, all alike, with 1 bisexual and 1-2 sterile, rudimentary florets. Glumes unequal, glabrous or scabrous; lower glumes 2.5-6 mm, 1/2 or more as long as the upper glumes; upper glumes 5.5-8 mm; lowest lemmas 3-6.5 mm, glabrous or scabrous-strigose, often minutely rugose, acute or inconspicuously 3-lobed, 3-veined, veins usually extending as short mucros or awns to 6 mm; central mucros or awns not flanked by membranous lobes; lowest paleas acute, unawned; anthers 1.5-3.5 mm, yellow, orange, red, or purple; distal floret (s) 0.4-3.5 mm, sterile, variable, usually a glabrous lemma having a short membranous base, no palea, and 3 unequally-developed awns, central awns 1.5-7 mm. 2n = (20), 40, 41-103.
Conn., N.J., N.Y., W.Va., Alta., B.C., Man., Ont., Sask., D.C., Wis., Idaho, Maine, S.C., Pacific Islands (Hawaii), Oreg., Fla., Wyo., N.Mex., Tex., La., N.C., Tenn., Pa., Ala., Ariz., Ga., Ill., Ind., Ky., Md., Mich., Minn., Miss., N.Dak., Nebr., Ohio, S.Dak., Utah, Ark., Wash., Va., Colo., Calif., Kans., Okla., Iowa, Mo., Mont.
Bouteloua curtipendula is a common, often dominant or co-dominant species in open grasslands and wetlands of the drier portions of the central grasslands of North America. It is highly regarded as a forage species and is also an attractive ornamental. Its range extends from the Flora region through Mexico and Central America to western South America.
As the range of chromosome numbers suggests, B. curtipendula is an apomictic species. There are three varieties. Two of the three grow in the Flora region; the third, B. curtipendula var. tenuis Gould & Kapadia, is endemic to Mexico.
"decumbent" is not a number.