Wet mt. meadows, gulches and moist places on mt. slopes, in N. M. (San 

 Miguel, Taos, and Lincoln cos.) and Ariz. (Graham Co.); Colo., Ut., N. M. 

 and Ariz. 



3. Trisetum spicatum (L.) Richt. Spike trisetum. Fig. 102. 



Culms densely tufted, erect, 15-50 cm. tall, glabrous to puberulent; sheaths 

 and usually the blades puberulent; panicle dense, usually spikelike, often inter- 

 rupted at base, pale or often dark purple, 5-15 cm. long; spikelets 4-6 mm. long; 

 glumes somewhat unequal in length, glabrous or scabrous except the keels, or 

 sometimes pilose, the first narrow, acuminate and 1-nerved, the second broader, 

 acute and 3-nerved; lemmas scaberulous, 5 mm. long, the first longer than the 

 glumes, the teeth setaceous; awn attached about one third below the tip, 5-6 mm. 

 long, geniculate, exserted. 



Wet alpine meadows and slopes, in N. M. (Mora, Rio Arriba and Sandoval 

 COS.) and Ariz. (Apache and Coconino cos.); Arctic America, southw. to Conn., 

 Pa., Mich, and Minn., in the mts. to N. M., Ariz, and Calif.; also w. N. C; 

 through Mex. to the Antarctic regions of S. A.; arctic and alpine regions of the 

 Old World. 



23. Deschampsia Beauv. Hair-grass 



Low or moderately tall annuals or usually perennials with shining pale or 

 purplish spikelets in narrow or open panicles; spikelets 2-flowered, disarticulating 

 above the glumes and between the florets, the hairy rachilla prolonged beyond 

 the upper floret and sometimes bearing a reduced floret; glumes about equal, 

 acute or acutish, membranaceous; lemmas thin, truncate and 2- to 4-toothed at 

 summit, bearded at base, bearing a slender awn from or below the middle, the 

 awn straight, bent or twisted. 



About 60 species in temperate and cold regions, and in tropical mountains, in 

 both hemispheres. 



1. Annual; panicle open, the stiffly ascending capillary branches usually in 

 twos 1. D. danthonioides. 



1. Perennials; panicle narrow or open, the slender branches appressed or droop- 



ing (2) 



2(1). Glumes usually longer than the florets; panicle usually narrow, as much as 



3 dm. long, the branches appressed; blades filiform, lax 



2. D. elongata. 



2. Glumes shorter than the florets; panicle open, nodding, 1-2.5 dm. long, the 



branches drooping; blades firm, flat or folded 3. D. caespitosa. 



1. Deschampsia danthonioides (Trin.) Munro ex Benth. Annual hairgrass. 



Annual; culms slender, erect. 15-60 cm. tall; blades few, short, narrow; panicle 

 open, 7-25 cm. long, the capillary branches commonly in twos, stiflly ascending, 

 naked below, bearing a few short-pediceled spikelets toward the ends; glumes 4-8 

 mm. long, 3-nerved, acuminate, smooth except the keel, exceeding the florets; 

 lemmas smooth and shining, somewhat indurate, 2-3 mm. long, the base of the 

 florets and the rachilla pilose, the geniculate awns 4-6 mm. long. 



In mud about lakes and ponds, along streams and wet meadows, in Ariz. 

 (Coconino and Cochise cos.); Mont, to Alas., s. to Ariz, and Baja Calif.; Arg. 

 and Chile. 



2. Deschampsia elongata (Hook.) Munro ex Benth. Slender hair grass. 



Perennial; culms densely tufted, slender, erect, 3-12 dm. tall; blades soft, 

 1-1.5 mm. wide, flat or folded, those of the basal tuft filiform-involute; panicle 

 very narrow, 15-30 cm. long, the capillary branches strictly appressed; spikelets 

 on short appressed pedicels; glumes 4-6 mm. long, 3-nerved, as long as or 



222 



