110 MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



retrorsely pubescent, often purple, the collar often puberulent ; ligule 1 

 to 2 mm long; blades sometimes folded; panicle open, usually 5 to 10 

 cm long, the apex nodding, the branches mostly in twos or threes, 

 naked below; lemmas rather strongly nerved, glabrous or pubescent 

 on the lower part of the nerves. 2J. (P. wheeleri Vasey; P. olneyae 

 Piper.) Open woods at medium altitudes, Alberta and British 

 Columbia, south in the mountains to Colorado, New Mexico, and 

 California (fig. 178). Typical P. nervosa (including P, olneyae), found 

 mostly in Washington and 

 Oregon, has glabrous to 

 scaberulous strongly 

 nerved lemmas and gla- 

 brous sheaths, and a loose 

 open panicle, the capillary 

 lower branches in whorls 

 of 3 or 4, drooping, as 



much as 8 cm long; typi 

 cal P. wheeleri, original!] 



FIGURE 175. Poa atropurpurea. 

 Plant, X 1; floret, X 10. (Type.)J 



FIGURE 176. Poa curta. 



Panicle, X 1; floret, X 10. (Jones 

 5573, Utah.) 



described from Colorado, has firmer, less strongly nerved lemmas, 

 more or less pubescent on the lower part of the keel and marginal 

 nerves, and purplish retrorsely pubescent lower sheaths. These 

 characters are not coordinated and the forms grade into each other, 

 both as to characters and range. 



15. Poa kelloggii Vasey. (Fig. 179.) Culms 30 to 60 cm tall; 

 sheaths slightly scabrous; blades flat or folded, 2 to 4 mm wide; 

 panicle pyramidal, open, 7 to 15 cm long, the branches mostly 

 solitary or in twos, spreading or reflexed, bearing a few spikelets 

 toward the ends; spikelets rather loosely flowered, 4 to 6 mm long; 

 glumes 3 and 4 mm long; lemmas acute or almost cuspidate, 4 to 5 



