Calamagrostis erectifolia Hitchc.

Calamagrostis erectifolia Hitchcock, sp. nov
Culms in large dense tufts, erect, scabrous on the upper part, 1-1.5 m. tall; sheaths pale, glabrous or the upper scabrous; ligule 2-3 mm. long; blades erect, closely involute, scabrous, rigid, half as long as the culm, about 1 mm. thick; panicle open, pyramidal, mostly 15-20 cm. long, the axis scabrous, the branches capillary, flexuous, spreading or drooping, scabrous, naked below, as much as 10 cm. long, verticillate, the verticils 3-5 cm. apart; glumes narrow, acute, glabrous except the scabrous keel, 4-5 mm. long, the first 1 -nerved, the second 3-nerved; lemma lanceolate, glabrous or minutely scaberulous, about 4 mm. long, the awn wanting or reduced to a short often divergent point not extending beyond the tip of the lemma; callus-hairs rather abundant, about 1 mm. long; rachilla rather stout, short-pilose, 2-3 mm. long.
Culmi dense caespitosi erecti 1.5 m. alti; vaginae glabrae vel superiores scabrae; ligula 2-3 mm. longa; laminae erectae involutae scabrae rigidae elongatae 1 mm. crassae; panicula pyramidalis patens 15-20 cm. longa, ramis capillaribus flexuosis patulis scabris, inferne nudis, usque ad 10 cm. longis, verticillatis; glumae angustae 4-5 mm. longae; lemma lanceolatum glabrum vel minute scaberulum circa 4 mm. longum; arista nulla vel brevissima; pili calli 1 mm. longi; processus rachillae breviter pilosus 2-3 mm. longus.
Type collected on partially open ground, Mount Nevada, Jalisco, altitude about 3000 meters, September 23, 1910, A. S. Hitchcock 7162 (U. S. Nat. Herb. no. 844948). Distribution: Mount Nevada and Mount Colima, Mexico.