Bouteloua alamosana Vasey

Bouteloua alamosana Vasey, Contr. U. S. Nat. Herb
1: 115. 1891.
Annual; culms in rather dense tufts, erect or usually decumbent-spreading, 6-40 cm. tall, branching, glabrous; sheaths mostly much shorter than the internodes, glabrous to papillosehispid; ligule cihate, about 0.5 mm. long; blades flat, 3-8 cm. long, mostly 2-3 mm. wide, nearly glabrous or usually papillose-pilose; axis of the inflorescence scabrous to densely pubescent; spikes 4-9, or fewer in depauperate specimens, stiffly ascending or spreading, falling entire, usually bearing 3 spikelets, the rachis densely pubescent at the base, ciliate, the back often villous; glumes acuminate, scabrous or hispid on the keel, the first 4—6 mm. long, the second 6-8 mm. long; lemma acute, 6-7 mm. long, not cleft, glabrous, the central awn about 2 mm. long, scabrous, the lateral ones a little shorter; palea a little longer than the body of the lemma, bifid, the keels scabrous; rudiment staminate, glabrous, deeply cleft, the lobes acuminate, the awns flattened toward the base, scabrous or hispid on the margins, 10-15 mm. long.
Type locality: Alamos, Sonora {Palmer 698 in 1890).
Distribution: Sonora; Honduras, Costa Rica, Nicaragua and Salvador.