HOW TO KNOW THE GRASSES 



35b. Ligxxles 3 — 7 mm. long; leai blades 2 — 6 mm. wide. Fig. 219. 



REDTOP Agrostis alba L. 



Perennial; culms up to 1 — 1.5 m. tall; nu- 

 merous creeping rhizomes present; panicle 

 pyramidal, with rather dense whorls of 

 branches, flowering to their bases. Redtop 

 is one of our most important meadow grasses, 

 and is also used in lawn seed mixtures. 

 Roadsides, meadows, waste ground; very 

 widely naturalized. June — August. Intro- 

 duced from Europe. 



Figure 219 



36a. Panicle narrow, with the short branches bearing spikelets nearly 

 to their bases 37 



36b. Panicle open, the spreading branches bearing spikelets at their 

 outer ends only 38 



37a. Slender alpine plants; leaf blades 5 cm. long or shorter, 1 — 2 mm. 

 wide; ligules 1 — 2 mm. long; panicles usually less than 5 mm. wide. 

 Fig. 220. 



Agrostis vanabilis Rydb. 



i. - 



Figure 220 



Perennial; tufted; culms 10 — 20 cm. tall; 

 panicles small, 2 — 6 cm. long; spikelets about 

 2.5 mm. long; lemmas about 1.5 mm. long; 

 palea very short. High altitudes in the moim- 

 tains, usually above timberline along creeks 

 and on slopes. Forage value good. July — 

 August. 



Agrostis humilis Vasey. Similar but smaller, 

 differing from the above chiefly in having a 

 palea about 2/3 as long as the lemma; plants 

 5 — 15 cm. tall; panicles purple, slender, 1 — 3 

 cm. long. Excellent forage. Bogs and moun- 

 tain meadows above timberline, Montana and 

 Washington to Colorado and Nevada. July — 

 August. 



117 



