420 



WEED FLORA OP IOWA, 



Figure 234B 



Figure 254A 



Fig. 254. A. Smooth Brome CBromus inermls). B. Awned Brome (.Bromus 



tectorum) . 

 (A, after Hillman ; B, drawn by Ada Hayden.) 



Awned Brome Grass (Bromus tectorum L.). 



Spikelet with unequal, acuminate-pointed, hirsute empty glumes, 

 and rough or hirsute flowering glumes 8-12 mm. long; awn 12-16 

 mm. long. 



Chess (Bromus secalinus It.). 



Spikelets tinged, 6-12-flowered, pendulous in fruit, one-twelfth 

 to two-fifths in. long ; empty glume oblong-lanceolate ; flowering 

 glume ovate-oblong, obscurely 7-nerved, nearly awnless, or short- 

 awned from the back of apex ; pubescent along margins and toward 

 the apex; palet obtuse, strongly nerved; toothed or fringed with 

 distant bristles; seed brownish. Pound in oats and other small 

 grain. 



Perennial Rye Grass {Lolium perenne L.). 



Spikelets about one-half in. in length, 5-12-flowered ; empty 

 glume much shorter than the spikelet; flowering glume obscurely 

 nerved, obtuse, cuspidate, or very short awn-pointed, bearing callus 

 at base ; palet granulate ; serrulate on margin. 



