210 



POACEAE 



35. Poa cusickii \^asev. 



Cusick's Bluegrass. 



Fig. 487. 



Poa cusickii Vasey, Contr. U. S. Nat. Herb. 1: 271. 1893. 



Poa filifolia Vasey, Contr. U. S. Nat. Herb. 1: 271. 1893, 

 not Schur, 1866. 



Poa idahoensis Beal, Grasses N. Am. 2: 539. 1896. 



Poa scabrifolia Heller, Bull. Torrey Club 24: 310. 1897. 



Poa spillmani Piper, Erythea 7: 102. 1899. 



Poa capillarifolia Scribn. & Williams, U. S. Dept. Agr. Div. 



Agrost. Circ. 9: 1. 1899. 

 Poa cottoni Piper, Proc. Biol. See. Washington 18: 146. 1905. 



Perennial ; culms tufted, erect, smooth, or scabrous 

 helow the panicle, 25-50 cm. tall; sheaths smooth; 

 lilades filiform, scabrous ; panicle somewhat open, 3-8 

 cm. long ; spikelets 7-9 mm. long ; lemmas smooth, 

 4-5 mm. long. 



O Open woods and rocky slopes, in the Arid Transition Zone; 



eastern Washington to Oregon and Idaho. May-Tune. Type 



locality: Oregon. 



36. Poa pringlei Scribn. 



Pringle's Bluegrass. 



Fig. 488. 



Poa pringlei Scribn. Bull. Torrey Club 10: 31. 1883. 

 Poa argentea Howell, Bull. Torrey Club 15: 11. 1888. 

 Poa suksdorfii Vasey; Beal, Grasses N. Am. 2: 574. 1896. 



Tufted perennial ; culms 10-20 cm. tall, the base 

 sometimes decumbent and rhizome-like; sheaths 

 smooth, loose and papery ; blades mostly basal, in- 

 volute, usually not over 2-5 cm. long, smooth, the 

 uppermost culm blade at or below the middle ; panicle 

 narrow, contracted, few- to several-flowered, short- or 

 long-exserted ; spikelets 6-8 mm. long, about 3- 

 flowered ; glumes equal, broad, 3-nerved, 4—5 mm. 

 long ; lemmas 5-6 mm. long, smooth or scabrous, not 

 webbed nor pilose. 



Rocks and sand, in the Alpine Zone; summits of mountains, 

 Washington, south through the Sierra Nevada to the Mount 

 Whitney region of California. July-Aug. Type locality: 

 headwaters of the Sacramento River. 



37. Poa leibergii Scribn. 

 Leiberg's Bluegrass. Fig. 489. 



Poa leibergii Scribn. U. S. Dept. Agr. Div. Agrost. Btill. 8: 6. pi. 2. 



1897. 

 Poa hanseni Scribn. U. S. Dept. Agr. Div. Agrost. Bull. 11: 53. pi. 9. 



1898. 

 Poa pringlei hanseni Smiley, Univ. Calif. Publ. 9: 104. 1921. 



Tufted perennial ; culms 7-20 cm. tall ; sheaths smooth ; 

 ligule about 2 mm. long; blades mostly basal, firm, involute. 

 smooth, short ; panicle narrow, 2-5 cm. long, usually purple, 

 the branches short, appressed ; spikelets 4-6 mm. long; 

 glumes about 3 mm. long; lemmas 3 mm. long, smooth or 

 scaberulous. 



Alpine meadows and sterile gravelly ali)ine flats in the Hudsonian 



Zone; Malheur County, Oregon, through the Sierra Nevada to the 



Mount Whitney region, California. June-July. Type locality: Mal- 

 heur County, Oregon. 



