378 MISC. PUBLICATION 200, IT. S. DEPT. OF AGRICULTURE 



yons, rocky hills, and mesas, New 



Mexico and Arizona to central 

 Mexico. 



,36. Muhlenbergia 

 polycaulis Scribn. 

 (Fig. 786.) Perennial, 

 from a firm crown ; culms 

 numerous, wiry, decum- 

 bent and scaly at base, 

 30 to 50 cm tall : blades 



Figure 780.— Muhlenbergia andina. Plant, X 1; glumes and 

 floret, X 10. (Elmer 558, Wash.) 



Figure 781.— Distribution of 

 Muhlenbergia andina. 



mostly flat and less than 

 5 cm long, about 1 mm 

 wide; panicle narrow, 

 contracted, interrupted, 

 3 to 8 cm long; spike- 

 lets, excluding awns, 

 2.5 to 3 mm long, the 

 glumes a little shorter, 

 tapering to slender awn- 

 the lemma tapering into 



tips; lemma and palea loosely villous belo^ 

 a delicate awn 1 to 2 cm long. % — 

 Shaded ledges and grassy slopes, western 

 Texas; southern Arizona to central 

 Mexico. 



37. Muhlenbergia arsenei Hitehc. 

 (Fig. 787.) Perennial, without rhizomes 

 but the spreading base sometimes rhi- 

 zomatous in appearance, loosely tufted; 

 culms wiry, 10 to 30 cm tall, branched 

 below, the branches erect ; leaves crowded 

 toward the base, the blades slender, invo- 

 lute, sharp-pointed, 1 to 3 cm long; pan- 

 icle narrow, rather loose, purplish, 2 to 

 10 cm long, the branches ascending, 

 floriferous from base; spikelets, excluding 

 the awns, 4 to 5 mm long, the glumes 

 shorter, acute or subacute, awnless; lem- 

 ma sparsely pubescent below, tapering 

 into a flexuous awn 6 to 10 mm long. 

 Ql — Arid slopes, northern New Mexico 

 and southeastern Utah. 



38. Muhlenbergia monticola Buckl. 

 Mesa muhly. (Fig. 788.) Perennial; 

 culms tufted, slender, erect or decum- 

 bent at base, 30 to 50 cm tall, branching at 

 the lower and middle nodes, leafy through- 

 out; blades 3 to 7 cm long, narrow, flat, or soon involute; panicle soft, 



Figure 782.— Muhlenbergia jonesii. 

 Plant, X 1; glumes and floret, X 10. 

 (Austin 1230, Calif.) 



