HOW TO KNOW THE GRASSES 



108b. Lemmas pubescent on the nerves and also between them near 

 the base. Fig. 144. 

 PLAINS BLUEGRASS Poa arida Vasey 



Perennial; producing rhizomes; culms 20 — 

 60 cm. tall; leaf blades borne mostly near 

 the base of the plant, folded, 2 — 3 mm. wide; 

 panicle dense, cylindrical, 2 — 10 cm. long, 

 with short branches; spikelets 5 — 7 mm. long, 

 the first glume with one nerve; anthers about 

 1.5 mm. long. Salty or alkaline meadows, 

 up to 3000 m. elevation; an important forage 

 grass on the Great Plains. Jime — ? 



Poa glaucifolia Scribn. & Will, is similar. 

 The first glume has 3 nerves; anthers about 

 2.5 mm. long; panicles more open; herbage 

 glaucous. Moist ground and open woods; 

 Minn, to B. C., to Nev. and N. M. 



Figure 144 



109a. Lemmas bearing a web of cottony hairs at the base; sheaths 

 glabrous 110 



109b. Lemmas without a web of hairs; lower sheaths glabrous or pu- 

 bescent. Fig. 145. 



Poa neivosa (Hook.) Vasey 



Perennial; producing rhizomes; culms 30 

 — 70 cm. tall, in large, leafy tufts; leaf 

 blades flat or folded; Hgules 1 — 2 mm. 

 long; panicles open, usually 5 — 10 cm. 

 long, with drooping branches which are 

 naked at the base. The lemmas vary from 

 entirely glabrous to hairy on the nerves or 

 scaberulous. This species is highly vari- 

 able in the hairiness of both sheaths and 

 lemmas. In common with most of the na- 

 tive and introduced bluegrasses, it is a 

 valuable forage plant for domestic graz- 

 ing animals and wild herbivores. Dry soil 

 in open woods, intermediate altitudes. May 

 — August. 



Figure 145 



110a. Panicles open, the long branches naked at the bases Ill 



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