MANUAL OF THE GRASSES OF THE UNITED STATES 135 



Figure 256.— Distribution of 

 Poa secunda. 



rather prominent; blades rather short, soft, flat, folded, or involute; 

 panicle narrow, 2 to 10 cm long, the branches short, appressed, or 

 somewhat spreading in an thesis; spikelets about as m P. gracillima. 

 % {P. sandbergii Vasey.)— Plains, dry woods, rocky slopes, at me- 

 dium and upper altitudes, but not strictly alpine, North Dakota to 

 Yukon Territory, south to Nebraska, New Mexico, Utah, Nevada, 

 and southern California; Chile (fig. 256). 



60. Poa canbyi (Scribn.) Piper. Canby bluegrass. (Fig. 257.) 

 Green or glaucous; culms 50 to 120 cm tall; ligule 2 to 5 mm long; 

 blades flat or folded; panicle narrow, compact or rather loose, 10 to 



15 cm long, sometimes as 

 much as 20 cm, the branches 

 short, appressed; spikelets 

 3- to 5-flowered; lemmas 

 more or less crisp-pubescent 

 on lower part of back. % 

 (P. lucida Vasey; P. laevi- 

 gata Scribn.) — Sandy or dry 

 ground, Michigan (Isle 

 Royal) and Minnesota to 

 Yukon Territory, south to 

 western Nebraska, Colo- 

 rado, Arizona, eastern Ore- 

 gon, and eastern Washing- 

 ton; Quebec (fig. 258). Poa 

 lucida has a slender but 

 somewhat loose pale or shin- 

 ing panicle; P. canbyi has 

 a denser, compact, dull 

 green panicle, but the two 

 forms grade into each other. 

 Poa lucida is more common 

 in Colorado and Wyoming ; 

 P. canbyi more common in 

 Montana. The pubescence 

 on the lemma may be obvi- 

 ous or obscure. 

 7. Nevadenses. — Perennials, without rhizomes, 

 tufted ; spikelets little compressed, narrow, 

 much longer than wide; lemmas convex 

 on the back, glabrous or minutely sca- 

 brous, not crisp-puberulent ; keels obscure, 

 marginal and intermediate nerves usu- 

 ally faint. 



61. Poa nevadensis Vasey. Nevada bluegrass. (Fig. 259.) 

 Culms erect, 50 to 100 cm tall; sheaths scabrous, sometimes only 

 slightly so ; ligule about 4 mm long, shorter on the innovations, decur- 

 rent; blades usually elongate, narrow, involute, sometimes almost 

 capillary, rather stiff; panicle narrow, 10 to 15 cm long, pale, rather 

 loose, the branches short-appressed ; spikelets 3 -to 5-flowered, 6 to 8 

 mm long; glumes narrow, the second about as long as the lowest floret; 

 lemmas 4 to 5 mm long, rather obtuse at the scarious tip. % — Low 



mmm 



Figure 255. Poa setunda. 

 Plant, X 1; floret, X 10. 

 (Hitchcock 23202, Wyo.) 



Figure 257.— Poa canbyi. 

 Panicle, X 1; floret X 10, 

 (Williams 2787, Wyo.) 



Figure 258.— Distribution of 

 Poa canbyi. 



