POACEAE. 33 



Tribe 7. AVENEAE. 



32. DESCHAMPSIA Beauv. HAIRGRASS. 



Empty glumes not extending beyond the apex of the upper flowering glume; 



leaves narrow. 

 Empty glumes 4-5 mm. long ; awn from half longer than to twice as long as 



the flowering glume. i. D. alpicola. 



Empty glumes 3-4 mm. long. 



Awn about half longer than the flowering glume; leaves short, almost fili- 

 form ; plant 2-3 dm. high. 2. D. curtifolia. 

 Awn slightly if at all exceeding the flowering glume ; leaves long and firm ; 



plant usually 3-8 dm. high. 3. D. caespitosa, 



Empty glumes much exceeding the upper flowering glume ; leaves broad. 



4. D. atropurpurea. 



1. Deschampsia alpicola Rydb. (D. caespitosa alpina Vasey; not D. alpina 

 R. & S.) In alpine meadows and on slopes, from Colo, to southern Wyo. and 

 Utah; a similar, if not identical, form in Alaska. Alt. 9000-14,000 ft. Bert- 

 houd's Pass; Twin Lakes; Pike's Peak; Silver Plume; South Park; near 

 Pagosa Peak; East River; Seven Lakes; Mt. Ouray; Georgetown; Cache la 

 Poudre, Larimer Co. ; Tennessee Pass ; Dead Lake ; vicinity of Gray's Peak ; 

 Clear Creek; Cameron Pass; Gray's Peak; Ethel Peak, Larimer Co. 



2. Deschampsia curtifolia Scribn. (D. brachyphylla Nash, in part.) On 

 wet alpine slopes from Mont, to Colo. Alt. 11,000-12,000 ft. Little Kate 

 Mine, La Plata Mountains; crater of Mt. Richtofen. 



3. Deschampsia caespitosa (L.) Beauv. In wet meadows and swamps from 

 Newf. to Alaska, N. J. and Calif. Alt. 7500-11,000 ft. Twin Lakes; George- 

 town ; Pagosa Springs ; Cache la Poudre, Larimer Co. ; Hamor's Lake ; North 

 Park; Gunnison; Marshall Pass; Ruxton Park; Grizzly Creek; Steamboat 

 Springs; Silver Plume; Pike's Peak; Como; North Park; Deadman Canon; 

 near Chambers' Lake; Fort Collins; Barnes' Camp; Ragged Mountains, Gun- 

 nison Co.; Hahn's Peak, Routt Co.; summit of North Park Range. 



4. Deschampsia atropurpurea (Wahl.) Scheele. In alpine and subarctic 

 meadows from Lab. to Alaska, northern N. Y. and Calif. Alt. about 10,000 

 ft Buffalo Pass, near Divide, Routt Co. 



33. TRISETUM Pers. FALSE OATS. 



Leaf-sheaths and blades long-hairy ; upper part at the stem densely pubescent. 



i. T. subspicatum. 

 Leaf-sheaths and blades glaborous or the lowest sheath short-pubescent, with 



reflexed hairs ; stem glabrous or slightly scabrous in the inflorescence. 

 Inflorescence long, dense, cylindric ; lower empty glume only slightly narrower 

 than the upper ; leaf-blades not much broader than the sheaths and without 

 conspicuous auricles. 2. T. ma jits. 



Inflorescence lanceolate, open ; lower empty glume scarcely more than half as 

 broad as the upper ; leaf-blades much broader than the sheaths and there- 

 fore with conspicuous auricles at the base. 3. T. montanum. 



i. Trisetum subspicatum (L.) Beauv. (T. subspicatum molle Coult.) On 

 mountains and hillsides from Greenl. to Alaska, N. H., Colo, and Calif. ; 

 also in northern Europe. Alt. 10,000-13,000 ft. Twin Lakes; Valley Spur; 

 Seven Lakes; Georgetown; Gray's Peak; Cameron Pass; Pike's Peak; Dead 



