MANUAL OF THE GRASSES OF THE UNITED STATES 59 



Lemmas awnless or with an awn rarely as much as 2 mm. long. 



Spikelets oblong to linear, mostly 8- to 10-flowered and more than 10 mm. long. 



17. F. ELATIOR. 

 Spikelets ovate or oval, mostly not more than 5-flowered, less than 10 mm. long. 

 Lemmas acuminate, sometimes with an awn as much as 2 mm. long, membranaceous, 



distinctly nerved, 6 to 9 mm. long 18. F. sororia. 



Lemmas awnless, obtuse to acutish, rather firm, indistinctly nerved. 



Lemmas 5 to 7 mm. long, acutish 19. F. versuta. 



Lemmas about 4 mm. long, relatively blunt, rather turgid. 



Spikelets loosely scattered in a very open panicle with long slender branches. 



20. F. OBTUSA. 



Spikelets somewhat aggregate toward the ends of rather short branches of a less 



open nodding panicle - 21. F. paradoxa. 



lb. Blades involute or if flat less than 3 mm. wide (sometimes flat in F. calif orm'ca, but firm 

 and soon involute). 

 Ligule 2 to 4 mm. long or longer. Lemmas awnless or cuspidate. 



Lemmas 7 mm. long _ 22. F. thurberi. 



Lemmas 4 mm. long 23. F. ligulata. 



Ligule short. 



Collar and mouth of sheath villous. Culms tall and stout (rather short in var. parishii). 



25. F. CALIFORNICA. 



Collar and mouth of sheath not villous. 



Panicle branches densely ciliate on the angles. Blades about 1 mm. wide, flat or 



folded 26. F. dasyclada. 



Panicle branches not ciliate on the angles. 



Culms decumbent at the usually red, fibrillose base, in loose tufts. Awn of lemma 



shorter than the body; blades smooth 28. F. rubra. 



Culms erect. 



Lemmas 7 to 10 mm. long, scabrous. Culms densely tufted, rather stout, usually 

 scabrous below the panicle; lemmas acute, rarely short-awned. 



24. F. SCABRELLA. 



Lemmas mostly not more than 7 mm. long. 

 Lemmas awnless (see also F. arizonica). 



Lemmas 6 to 7 mm. long; culms slender, loosely tufted. 



27. F. VIRIDULA. 



Lemmas about 3 mm. long 31. F. capillata. 



Lemmas awned. 



Awn as long as or longer than body of the lemma; blades soft, glabrous, 



sulcate 29. F. occidentalis. 



Awn shorter than body of the lemma; blades slender, numerous, usually 

 scabrous. 

 Blades mostly not more than half as long as the culms; panicle narrow, 

 often almost spikelike, few-flowered, mostly less than 10 cm. long; 



culms mostly less than 30 cm. tall 30. F. ovina. 



Blades elongate; panicles 10 to 20 cm. long, somewhat open; culms 30 to 

 100 cm. tall. 



Awn 2 to 4 mm. long 32. F. idahoensis. 



Awn short or obsolete 33. F. arizonica. 



Section 1. Vulpia (Gmel.) Reichenb. 



Slender annuals; lemmas awned; sta- 1. Festuca octoflora Walt. Six- 



mens usually 1, sometimes 3; weeks fescue. (Fig. 43.) Culms 



flowers usually self-pollinated, erect, usually 15 to 30 cm. tall, 



but young panicles are found with sometimes as much as 60 cm.; blades 



anthers and stigmas exserted. narrow, involute, 2 to 10 cm. long; 



Some of the species, especially panicle narrow, the branches short, 



numbers 7 to 13, resemble each appressed or spreading; spikelets 6 



other closely. The differences, to 8 mm. long, densely 5- to 13- 



though small, appear to be con- flowered ; glumes subulate-lanceolate, 



stant, hence the recognizable the first 1-nerved, the second 3- 



forms are maintained as species, nerved, 3 to 4.5 mm. long; lemmas 



rather than reduced to varieties firm, convex, lanceolate, glabrous or 



under leading species. scabrous, 4 to 5 mm. long, the mar- 



