Slender Hairgrass

Deschampsia elongata (Hook.) Munro; Benth. PI. Hartw 342. 1857.
Aira elongata Hook. Fl. Bor. Am. 2: 243. 1840.
Deyeuxia Schaffneri Fourn. Bull. Soc. Bot. Fr. 24: 181. 1877; Mex. PI. Gram. 107. 18S6. (Type
from Mount Orizaba, Schaffntr 94.) Deschampsia elongata var. ciliata Vasey; Beal, Grasses N. Am. 2: 371. 1896. (Type from Santa
Cruz, California, Anderson.) Deschampsia elongata var. tenuis Vasey; Beal, Grasses N. Am. 2: 372. 1896. (Type from Santa
Cruz, California, Jones 3201.) Deschampsia ciliata Rydb. Fl. Rocky Mts. 60. 1917. (Based on D. elongata var. ciliata Vasey.) Aira Vaseyana Rydb. Fl. Rocky Mts. ed. 2. 1112. 1922. (Based on Deschampsia elongata var.
ciliata Vasey.)
Perennial; culms densely tufted, slender, erect, glabrous, 30-120 cm. tall; sheaths glabrous, striate ; ligules acute, about 5 mm. long; blades soft, flat or folded, glabrous or scaberulous, 1-1.5 mm. wide, those of the basal tuft filiform; panicle narrow, as much as 30 cm. long, the axis scabrous, the capillary branches appressed, rather loosely flowered ; glumes 3-nerved, acuminate, usually somewhat exceeding the florets, minutely scabrous, 4—6 mm. long; lemmas 2-3 mm. long, simitar to those of D. danthonioides, the awns shorter, straight, the callus-hairs half as long as the lemma, the rachilla-joint pilose.
Type locality: Columbia River (Douglas).
Distribution: Open ground, Alaska to Wyoming, and southward to Arizona, California, and northern Mexico; also in Chile.