234 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



sachusetts (Harwich); ballast, New 

 Jersey and Oregon; introduced from 

 Europe. 



4. Agropyron pseudorepens Scribn. 

 and Smith. (Fig. 308.) Resembling 

 .4 . repens, often stouter, the rhizomes 

 not yellow; blades commonly nar- 

 rower; spike 10 to 20 cm. long, the 

 spikelets contracted and appressed, 

 the flat or scarcely keeled glumes 2 

 to 2.5 mm. wide, nearly equaling the 

 spikelets; lemmas scaberulous to mi- 

 nutely hispidulous, rachilla villous. 

 % — Mostly in bottom lands or 

 valleys, Alberta; Michigan (south 

 shore of Lake Superior); South Da- 

 kota and Nebraska to Washington, 

 south to New Mexico and Arizona. 

 Specimens without rhizomes resemble 

 A. trachycaulum. 



5. Agropyron smithii Rydb. West- 

 ern wheatgrass. (Fig. 309.) Usually 

 glaucous; culms erect, 30 to 60 cm. 

 tall, sometimes taller, with creeping- 

 rhizomes; sheaths glabrous; blades 

 firm, stiff, mostly flat when fresh, 

 involute in drying, strongly nerved, 

 scabrous or sometimes sparsely vil- 

 lous on the upper surface, mostly 2 

 to 4 mm. wide, tapering to a sharp 

 point; spike erect, mostly 7 to 15 

 cm. long, the rachis scabrous on the 



Figure 308. 



Agropyron pseudorepens, X 1. (Chase 

 5389, Colo.) 



angles; spikelets rather closely im- 

 bricate, occasionally two at a node, 

 6- to 10-flowered, 1 to 2 cm. long, 

 the rachilla scabrous or scabrous- 

 pubescent; glumes rigid, tapering to 

 a short awn, rather faintly nerved, 

 10 to 12 mm. long; lemmas about 1 

 cm. long, firm, glabrous, often pubes- 



Figure 309. — Agropyron smithii, X 1. (Nelson 3918, Wyo.) 





