116 MISC. PUBLICATION 200, U. S. DEFT. OF AGRICULTURE 



FIGURE 190. Poa trivialis Panicle, X 1; floret, X 10. (Coville, N.Y.) 



3. PaMstres. Perennials without creeping rhizomes; lemmas webbed 

 at base, glabrous, or pubes- 

 cent on the nerves. 

 22. Poa trivialis L. ROUGH 



BLUEGRASS. (Fig. 190.) Culms 



erect from a decumbent base, 



often rather lax, scabrous below 



the panicle, 30 to 100 cm tall; 



sheaths retrorsely scabrous or 



scaberulous, at least toward the 



summit; ligule 4 to 6 mm long; 



blades scabrous, 2 to 4 mm wide; 



panicle oblong, 6 to 15 mm long, 



FIGURE 191. Distribution of 

 Poa trivialis. 



the lower branches about 5 in a 

 whorl; spikelets usually 2- or 3- 

 flo wered, about 3 mm long ; lemma 

 2.5 to 3 mm long, glabrous except 

 the slightly pubescent keel, the 

 web at base conspicuous, the 

 nerves prominent. <4 Moist 

 places, Newfoundland and On- 

 tario to Virginia, West Virginia, 

 Michigan, South Dakota, and on 

 the Pacific coast from southern 



Alaska to northern California; On FIGURE 192Poo marcida. Panicle, X I; floret, X 10. 



ballast, Louisiana (fig. 191);intro- 



duced from Europe. Sometimes used in mixtures for meadows and 



pastures under the name rough-stalked meadow grass, 



