MANUAL OF THE GRASSES OF THE UNITED STATES 



381 



ally 2 to 3 mm.), 1-nerved, acuminate; 

 lemma 4 to 5 mm. long, 3- to 5- 

 nerved, scabrous, especially on the 

 nerves, sparsely to rather densely 

 appressed-pubescent on the inter- 

 nerves toward the base; awn 10 to 20 

 mm. long (rarely less). O (M. 

 depauperate, of Manual, ed. 1.) — Open 

 ground at higher elevations, Colorado 

 and Texas to Arizona; Mexico. 



13. Muhlenbergia filiformis 

 (Thurb.) Rydb. Pull-up muhly. 

 (Fig. 532.) Annual, or sometimes ap- 

 pearing perennial, loosely tufted, 

 rather soft and lax, erect or somewhat 

 spreading; culms filiform, usually 5 to 

 15 cm. tall, sometimes as much as 30 

 cm.; ligule about 2 mm. long; blades 

 flat, usually less than 3 cm. long; pan- 

 icle narrow, interrupted, few-flow- 

 ered, usually less than 5 cm. long; 

 glumes ovate, 1 mm. long; lemma 

 lanceolate, acute, mucronate, 2 mm. 

 long, minutely pubescent, scaberulous 

 at tip. O — Open woods and 



mountain meadows, South Dakota 

 and Kansas to British Columbia, 

 south to New Mexico and California. 

 A somewhat stouter form with thicker 

 panicles has been differentiated as M. 

 simplex Rydb. 



14. Muhlenbergia repens (Presl) 

 Hitchc. Creeping muhly. (Fig. 533.) 

 Perennial with widely creeping scaly 

 rhizomes; culms decumbent, branch- 

 ing, spreading, the flowering branches 

 5 to 20 cm. long; blades mostly 1 to 3 



Figure 531. 



-Muhlenbergia brevis. Plant, X 1 ; glumes 

 and floret, X 10. (Type.) 



Figure 532. — Muhlenbergia fili- 

 formis. Plant, X 1; glumes and 

 floret, X 10. (Nelson 4011, Wyo.) 



cm. long, flat or soon involute; pan- 

 icle narroAV, 1 to 4 cm. long, some- 

 times longer, interrupted; spikelets 

 about 3 mm. long; glumes more than 

 half as long as the lemma or a little 

 more, acutish; lemma narrowed to a 

 more or less apiculate summit, mi- 

 nutely roughened, usualfy darker than 

 the glumes, the lateral nerves obscure. 

 % - — Dry rocky or sandy open 

 ground, Texas to Arizona; Mexico. 



15. Muhlenbergia utilis (Torr.) 

 Hitchc. Aparejo grass. (Fig. 534.) 

 Similar to M . repens; usually more 

 delicate and more widely spreading 

 with finer leaves, the blades mostly 1 

 mm. wide or less; spikelets about 2 

 mm. long, less pointed, the glumes 



