MANUAL OF THE GRASSES OF THE UNITED STATES 233 



Figure 443.— Distribution of 

 Agropyron repens. 



3. Agropyron ptingens (Pers.) Roem. and Schult. (Fig. 442, B.) 

 Glaucous, culms 50 to 80 cm tall, with pale or brownish rhizomes; 

 blades firm, mostly involute, scabrous on the upper surface ; spikelets 

 awnless, compressed, often as much as 10-flowered, the florets closely 

 imbricate ; glumes firm, acute, obscurely nerved, 

 scabrous on the keel. % — Seacoast, Maine 

 (Cape Elizabeth), Mas- 

 sachusetts (Harwich), 

 Oregon (Linn ton) ; in- 

 troduced from Europe. 

 4. Agropyron arenic- 

 ola Davy. (Fig. 444.) 

 Culms low, more or less 

 spreading, 10 to 20 cm 

 tall, with slender exten- 

 sively creeping rhizomes; blades involute, 

 mostly longer than the culms, pungent-pointed; 

 spike 2 to 5 cm long, the axis glabrous; spike- 

 lets few-flowered, about 15 mm long; glumes 

 narrowly lanceolate, nerveless, firm, narrowed 

 to a pungent point, ciliolate; lemmas about 1 

 cm long, obscurely nerved, scabrous toward 

 margin and summit. % — Sandy seacoast, 

 middle California. The structure of the spike- 

 let suggests that this species may belong to 

 Elymus though the spikelets are solitary at the 

 nodes of the rachis. 



5. Agropyron smithii Rydb. Bluestem. 

 (Fig. 445.) 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 

 villous 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 angles; spikelets rather closely imbricate, 

 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 

 pubescent near the base, obscurely nerved, acu- 

 minate, mucronate, sometimes short-awned; 

 palea scabrous-pubescent on the keels. % 

 — Moist, usually alkaline soil, New York ; Mich- 

 igan and Ohio to Alberta and Washington, south 

 to Texas, Arizona, and northeastern California; 

 mostly introduced east of Iowa and Kansas (fig. 

 446). Two varieties have been recognized. Agropyron smithii var. 

 molle (Scribn. and Smith) Jones. Lemmas and sometimes glumes more 

 or less pubescent. % — About the same range as the species. Agro- 

 pyron smithii var. palmeri (Scribn. and Smith) Heller. Lower sheaths 

 pubescent. % — Colorado to Utah, south to New Mexico and Arizona. 



/ 



Figure 444.— Agropyron arenic 

 ola, X 1. (Davy 6781, Calif.) 



