MANUAL OF THE GRASSES OF THE UNITED STATES 



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8. Muhlenbergia appressa C. O. long, or sometimes only 5 mm. long. 

 Goodding. (Fig. 527.) Culms 10 to 40 O — Rocky ledges and open ground, 

 cm. tall, erect or decumbent at base, Arizona (Apache County); Chihua- 

 much branched below; ligule lacerate, hua, Mexico. 

 2 to 3 mm. long; blades flat or folded, 

 1 to 4 cm. long, scabrous or puber- 

 ulent; panicles numerous, as much as 

 20 cm. long, very narrow, loosely 

 flowered, the branches appressed; 

 glumes 1 to 2 mm. long or sometimes 

 less, obtuse; lemma 4.5 to 6 mm. long, 

 scabrous above, densely pilose on the 

 callus and margins at the base; awn 

 10 to 30 mm. long. O — Canyons 

 and slopes, southern Arizona. Cleis- 

 togamous spikelets similar to those in 

 M . microsperma are common in the 

 lower reduced sheaths. 



Figure 527. — Muhlenbergia appressa. Plant, X 1; 

 glumes and floret, X 10. (Type.) 



9. Muhlenbergia pulcherrima 



Scribn. (Fig. 528.) Culms 10 to 25 

 cm. tall, erect, freely branching at 

 the base; sheaths scabrous, longer 

 than the internodes; ligule thin, 2 to 

 3 mm. long; blades flat, pubescent on 

 the upper surface, mostly less than 5 

 cm. long and 1 mm. wide; panicles 3 

 to 5 cm. long, the branches ascending 

 or appressed; first glume 0.5 to 1 mm. 

 long, acute or notched, the second 2 

 mm. long, 2- or 3-toothed; lemma 3 

 to 4 mm. long, narrow, acuminate, 

 minutely bifid, scabrous, pubescent 

 on the lower half of the margins; awn 

 slender, flexuous, mostly 10 to 15 mm. 



Figure 528. — Muhlenbergia pulcherrima. Plant, X 1 ; 

 glumes and floret, X 10. (Schroeder, Ariz.) 



10. Muhlenbergia pectinata CO. 



Goodding. (Fig. 529.) Culms 10 to 25 

 cm. long, erect to decumbent, some- 

 times rooting at the lower nodes, 

 freely branching, angular; sheath 

 margins often ciliate; ligule erose to 

 ciliate, about 0.5 mm. long; blades 

 flat to involute, 1 to 6 cm. long, 1 to 

 2 mm. wide, pubescent or sparsely 



