MANUAL OF THE GRASSES OF THE UNITED STATES 



239 



soft and papery; blades flat or loosely involute, mostly less than 10 

 cm long, 1 to 3 mm wide ; spike more or less flexuous, 4 to 7 cm long, 

 the rachis scabrous on the angles, slender, the middle internodes 

 usually 8 to 10 mm long; spikelets mostly 3 to 7 in each spike, rather 

 distant, the lower and middle ones (excluding 

 awns) about as long as two internodes, mostly 

 3- to 5-flowered, the rachilla joints minutely 

 scabrous, about 2 mm long ; glumes rather nar- 

 row, about 3-nerved on the exposed side, 7 to 

 8 mm long, tapering into a straight awn about 

 5 mm long; lemmas tapering into a scabrous, 

 strongly divergent awn 1.5 to 2.5 cm long; 

 palea 10 to 12 mm long. % — Stony slopes, 

 2,500 to 3,500 m, Sierra Nevada, Tulare County, to Sierra County, 

 Calif. 



17. Agropyron scribneri Vasey. Spreading wheatgrass 



Figure 461.— Distribution of 

 Agropyron bakeri. 



463.) Culms tufted, prostrate or decumbent-spreading, often flexuous, 



Figure 462.— Agropyron pringlei, X 1 

 (Pringle 504, Calif.) 



Figure 463.— Agropyron scribneri, X 1. (Shear 

 1179, Colo.) 



20 to 40 cm long ; blades flat or, especially on the innovations, loosely 

 involute, more or less pubescent, mostly basal, the 2 or 3 culm blades 

 usually less than 5 cm long, 1 to 3 mm wide; spike long-exserted, often 

 nodding or flexuous, dense, 3 to 7 cm long, the rachis disarticulating 

 at maturity, the internodes glabrous, 3 to 5 mm long, or the lowermost 



55974°— 35 16 



