HOW TO KNOW THE GRASSES 



23a. One or both glumes longer than the lemma (excluding the awn) 

 24 



23b. Glumes shorter than or equal to the lemma in length 39 



24a. Glumes both longer than the lemma, equal, strongly flattened and 

 keeled, V-shaped in cross section 25 



24b. Glumes either imequal or not strongly keeled, never with long 

 fringing hairs on the keel 26 



25a. Spikelets about 5 mm. long; glumes cut square at the tip, the mid- 

 nerve protruding as an awn; plants widespread, tufted. Fig. 209. 

 TIMOTHY Phleuzn pratense L, 



Perennial; tufted, the culms 50 — 100 cm. 

 tall, often with swollen, bulb-like bases. 

 The dense, cylindrical panicles are stiff 

 and somewhat bristly. Timothy is one of 

 the important hay meadow grasses in the 

 northern states, and is very widely estab- 

 lished in the wild as well, in the moister 

 portions of the country. June — July. 



i - 



Figure 209 



Phleum alpinum L. (ALPINE TIMOTHY), 

 with short, plump, dark colored panicles, 

 occurs in wet mountain meadows at high 

 altitudes in the West and from Greenland 

 to Alaska. 



25b. Spikelets 10 — 20 mm. long; coarse, stiff grasses of sand beaches; 

 rhizomes long and stiff. Fig. 210. 



AMERICAN BEACHGRASS Ammophila breviligulata Fernald 



Perennial; spreading by very long, stiff 

 rhizomes. The plants are coarse and tough. 

 Panicles dense and cylindrical, 10 — 20 cm. 

 long. The plants are highly important sand 

 binders ' on dunes along the Atlantic Coast 

 and on sand beaches of the Great Lakes. 

 July — September. 



Figure 210 



26a. Glumes not swollen near the base. 



27 



112 



