HESPEROSTIPA (Elias) Barkworth Needlegrass
Plants hermaphroditic, caespitose, perennial. Culms erect or ascending, glabrous to scabrous; internodes hollow, terete.
Leaves basal, not distinctly distichous; sheaths terete, margins open; auricles absent; ligules membranous; blades flat or
folded or involute, linear, lax. Panicles open or contracted, primary branches ascending (drooping with age).
Spikelets solitary, terete or laterally compressed, disarticulation above the glumes, awned, pedicellate;
florets 1, reduced floret absent, callus bearded; rachilla not extending beyond floret; glumes 2, (acuminate) 5-7-veined,
about equal, longer than floret, hairy, awned or awnless; lemmas 5-veined (inconspicuously), indurate, margins not
overlapping, hairy; apex obtuse, awned; awns (1) apical, curved and twisted; paleas 2-veined, nearly lemma length
. Stamens 3; anthers yellow. Caryopses elongate to linear, tan. Base chromosome number x=11.
A small genus of about 4 species. These taxa are part of the Mixed Prairie of the High Plains, the Palouse
Prairie, and Desert Grasslands.