MANUAL OF THE GRASSES OF THE UNITED STATES 255 



wide; spike slender, erect or somewhat nodding, 4 to 12 cm long, 

 usually about 5 mm thick (excluding awns), the slender rachis tardily 

 disarticulating; spikelets imbricate, appressed, mostly 2-flowered, about 

 1 cm long, excluding the awns; glumes very narrow, scabrous, slightly 

 divergent but not bowed out at base, the midnerve usually distinct; lem- 

 mas scabrous toward the apex, extend- 

 ing into slender straight awns 1 to 2 cm 

 long. Qj. Meadows and open ground, 



FIGURE 498. Distribution of 

 Elymus macounii. 



FIGURE 499. Elymus 

 aristatus, X 1. (Chase 

 4762, Idaho.) 



FIGURE 497. _ Elymus 

 macounii. Disartic- 

 ulating spike, X 1. 

 (Anderson, Mont.) 



FIGURE 500. Distribution of 

 Elymus aristatus. 



x i. (c om - 



Minnesota to Alaska and eastern Wash- 



ington, south to Iowa, Nebraska, New FlGURE ^- 



*\f i r-t Tf // mons 163, Del.) 



Mexico, and California (fig. 498). 



16. Elymus aristatus Merr. (Fig. 499-) Culms tufted, rather leafy, 

 erect, 70 to 100 cm tall; sheaths glabrous, blades flat, 5 to 10 mm wide; 

 spike erect, dense, 6 to 14 cm long, 5 to 10 mm thick, the rachis tardily 

 disarticulating; spikelets closely imbricate, of ten in threes, 1- to 2-flow- 

 ered, about 1 cm long, excluding the awns; glumes subsetaceous, sca- 

 brous, 10 to 20 mm long; lemmas slightly wider than in E. macounii, 

 sparsely scabrous at least on the upper half, the slender straight awn 

 10 to 20 mm long. Qj. Meadows and open slopes, at middle alti- 

 tudes, Idaho and Washington, south to Nevada and California (fig. 500). 



65974 36 - 17 



