Ml 



Figure 617.— Distribution of 

 Calamagrostis montanensis. 



312 MISC. PUBLICATION 200, U. S. DEFT. OF AGRICULTURE 



40 cm tall, sometimes taller, with slender creeping rhizomes; lower 

 sheaths rather papery, smooth; blades erect, mostly less than 2 mm 

 wide, more or less involute, scabrous, sharp-pointed; panicle dense, 

 erect, more or less interrupted, usually pale, 5 to 10 cm long; spikelets 

 4 to 5 mm long, the pedicels very scabrous; glumes acuminate, 

 scabrous; lemma nearly as long as the glumes, finely 

 4-tootned, the awn attached about 1 mm above base, 

 about equaling the lemma, slightly 

 geniculate and protruding from 

 side of glumes ; palea nearly as long 

 as the lemma; hairs of callus and 

 rachilla rather abundant, about 

 half as long as the lemma. 91 — 

 Plains and dry open ground, Man- 

 itoba to Alberta, south to South Da- 

 kota, Wyoming, and Idaho (fig. 617). 



8. Calamagrostis rubescens Buckl. Pinegrass. (Fig. 

 618.) Culms slender, tufted, 60 to 100 cm tall, with 

 creeping rhizomes ; sheaths 

 smooth, but pubescent on 

 the collar, sometimes ob- 

 scurely so ; blades erect, 2 to 



4 mm wide, flat or some- 

 what involute, scabrous; 

 panicle narrow, spikelike 

 or somewhat loose or in- 

 terrupted, pale or purple, 7 

 to 15 cm long; glumes 4 to 



5 mm long, narrow, acumi- 

 nate; lemma pale, thin, 

 about as long as glumes, 

 smooth, the nerves obscure, 

 the awn from near base, 

 geniculate, exserted from 

 side of glumes, 1 to 2 mm 



long above the bend, the callus hairs scant, about one- 

 third as long as the lemma; rachilla 1 mm long, the sparse 

 hairs extending to 2 mm. 01 — Open pine woods, 

 prairies, and banks, Manitoba to British Columbia, 



south to northern Colorado and central California (fig. 619). A val- 

 uable range grass. A large form with dense lobed panicle has been 



called C. cusickii Vasey. 



9. Calamagrostis porteri A. Gray. (Fig. 

 620.) Culms slender, 60 to 120 cm tall, with 

 slender rhizomes ; sheaths pubescent on the col- 

 lar; blades flat, spreading, lax, 4 to 8 mm wide; 

 panicle narrow but rather loose, erect or some- 

 what nodding, 10 to 15 cm long; glumes 4 to 6 

 mm long, scaberulous; lemma slightly shorter 

 than the glumes, toothed at apex, the awn from 

 near base, about as long as the lemma, bent and protruding from 

 side of glumes; palea about as long as the lemma; callus hairs 



Figure 616 — 

 Calamagros- 

 tis montanensis. 

 Panicle, X 1 ; 

 glumes and 

 floret, X 10. 

 (Scribner 363, 

 Mont.) 



Figure 618.— Calamagrostis rubescens. 

 Panicle, X 1; glumes and floret, X 10. 

 (Sandberg and Leiberg, Wash.) 



Figure 619. — Distribution of 

 Calamagrostis rubescens. 



