No. 81. 



POA NERVOSA (Hook.) Vasey; Festuca nervosa Hook. Fl. Bor. Amer. 251 



(1840?). 



Plant perennial, with a slender, stoloniferous rootstock. 



Culms erect, slender, smooth, naked ^ of the way below tlie panicle, 2 to 3 feet tall. 



Leaves of sterile shoots numerous, flat or conduplicate, scabrous above, rather thin 

 and flexible, 1 to 2 lines wide, 6 to 12 inches long : leaves of the culm usually 3; sheaths 

 close, smooth, striate, shorter than the long internodes; blades flat, scabrous on the 

 margins, 2 to 4 inches long ; ligule obtuse, 1 to 2 lines long. 



Inflorescence a loose, open, erect or somewhat flexuous panicle 3 to 5 inches long; 

 rays 2 to 4 at each of the 6 or 7 nodes, slender, slightly scabrous, 2 inches long or 

 less, bearing 2 to 5 spikelets near the extremities. 



Spikelets compressed, 4 to 5 lines long, rather loosely 4- to 8-flowered with a small 

 rudiment; empty glumes ovate, acute, carinate, hispid on the keels, 1J to 1£ lines 

 long, shorter than the lower florets ; floral glume lance-ovate, barely acute, scarious 

 margined, scabrous on the nerves or throughout, often villous below but not webbed, 

 5-nerved, 2 lines long; palet lance-oblong, ciliate on the keels, nearly equaling the 

 glume; grain linear, translucent, 1 line long. 



Plate LXXXI; a, spikelet; b, floret opened. 



Central California to British Columbia and east to Montana in the mountains. It 

 is described in Botany of California as P. stenantha Trim, but the specimens do not 

 agree with Trinius's description. It is a very common grass in open pine woods, and is 

 considered valuable foi? stock-grazing. 



