GRAMINEAE. 



Vol. I. 



3. Agropyron pungens (Pers.) R. & S. Coast 

 Wheat-grass. Fig. 688. 



Triticum pungens Pers. Syn. 1 : 109. 1805. 

 Agropyron pungens R. & S. Syst. 2: 753. 1817. 

 Agropyron tetrastachys Scribn. & Sm. Bull. U. S. Dept. 

 Agric. Div. Agrost. 4: 32. 1897. 



Glaucous. Culms rigid, slender, erect, ih -3° tall, 

 from a running rootstock ; sheaths shorter than the in- 

 ternodes, smooth and glabrous; ligule wanting; blades 

 erect, acuminate, s'-8' long, 2" or less wide, smooth 

 beneath, glaucous above, scabrous on the margins; 

 spikes long-exserted, 3-5' long, 4-sided; spikelets 

 crowded, 6"-io" long, 6-11-flowered, appressed to the 

 4-angled articulated rachis, the angles hispidulous; 

 empty scales lanceolate, 5" long, rough on the keel, 

 5-7-nerved; flowering scales lanceolate, keeled, rough 

 toward the apex, acute, awn-pointed or short-awned. 



Sandy beaches, coast of Maine. Introduced from 

 Europe. July-Aug. 



4. Agropyron Smithii Rydb. Western 

 Wheat-grass. Fig. 689. 



A. repens glaucum Scribn. Mem. Torr. Club, 5 : 57, 



in part. 1894. 

 A. spicatum Scribn. & Sm. Bull. U. S. Dept. Agric. 



Div. Agrost. 4: 33, in part. 1897. 



Pale green, glaucous. Culms li°-4° tall, erect, 

 from a slender creeping rootstock, smooth and 

 glabrous; sheaths shorter than the internodes, 

 smooth ; ligule a short membranous ring ; blades 

 erect, 2'-8' long, 2"-^" wide, acuminate, very- 

 scabrous above, smooth beneath, becoming invo- 

 lute when dry; spike long-exserted, strict, 4'-8' 

 long; spikelets crowded, divergent from the 

 rachis, compressed, lanceolate when closed, i'-i' 

 long, 6-12-flowered; empty scales acuminate, 

 awn-pointed, shorter than the spikelet, hispidu- 

 lous on the keel ; flowering scales s"-6" long, 

 acute or awn-pointed, glabrous or sparsely pu- 

 bescent. 



Moist land, Manitoba and Minnesota to British 

 Columbia, south to Missouri and Texas. 



5. Agropyron dasystachyum (Hook.) Vasey. 

 Northern Wheat-grass. Fig. 690. 



Triticum repens var. dasystachyum Hook. Fl. Bor. Am. 2 : 



254. 1840. 

 Agropyrum dasystachyum Vasey, Spec. Rept. U. S. Dept. 



Agric. 63: 45. 1883. 

 Agropyron subvillosum E. Nels. Bot. Gaz. 38 : 378. 1904. 



Glaucous, culms l°-3° tall, erect, from long running 

 rootstocks, simple, smooth and glabrous; sheaths shorter 

 than the internodes ; ligule very short ; blades 2'-o/ long, 

 i"-3" wide, flat, or becoming involute in drying, smooth 

 beneath, rough above; spike zk'-j' in length; spikelets 

 4-8-flowered; empty scales 3-5-nerved, lanceolate, acumi- 

 nate or short-awned, 3"-A,V long ; flowering scales broadly 

 lanceolate, 5-nerved, 4V-6" long, acute or short-awned, 

 densely villous. 



Hudson Bay to the Yukon, south to the Great Lakes, 

 Nebraska and Colorado. Summer. 



