Flora of the Palousc Region 



A. purpurea Nutt. Perennial, tufted, 15-40 cm. high: radical leaves 

 numerous; culm leaves about three, all strongly involute and filiform, scab- 

 rous: panicle loose, purplish, 10-20 cm. long: awns of the flowering glume 

 capillary, 5-10 cm. long, the central slightly longer than the others. Dry 

 soil near Snake River. 



26. STIPA. 



Inflorescence a panicle: spikelets 1 -flowered, narrow: flowering 

 glume 1, bearing a more or less bent awn which is spiral and 

 articulated at the base: grain narrow, free, tightly closed in the 

 flowering glume. 



S. viridula Trin. Perennial, tufted, .5-1 m. tall, dark green: leaf blades 

 involute, long-attenuate, 10-15 cm - l° n g> scabrous: sheath shorter than the 

 internodes, loose, smooth; ligule very short: panicle erect, rather dense, 8-20 

 cm. long, narrow, its base included in the uppermost sheath; the branches 

 mostly in pairs: spikelets 10-12 mm. long, purple tinged: flowering glume 

 sparselv appressed hairy, the awns 25-30 mm. long, bent near the middle, be- 

 low which they are pubescent. Grassy hillsides and pine woods, infrequent. 

 Our form is hardly typical. 



27. PHLEUM. 



Inflorescence a spike: spikelets i-flowered: empty glumes mem- 

 branous, compressed, keeled, the apex obliquely truncate, the 

 mid-nerve produced into an awn: flowering glume much shorter: 

 grain ovoid, free, enclosed in the flowering glume and palet. 



P. pratense L. Tall, erect, .6-1.5 m - tall: leaf blades 15-20 cm. long, 

 S-10 mm. wide, smooth or scabrous: spike narrowly cylindrical, erect, 5-15 

 cm. long: spikelets 2-5 mm. long: empty glumes ciliate on the keels which 

 are prolonged into short awns. Abundantly introduced. 



28. ALOPECURUS. 



Inflorescence a spike: spikelets i-flowered, flattened: empty 

 glumes acute, sometimes short-awned: flowering glume 3-nerved, 

 awned on the back, usually with a palet. 



A. pallescens Pipern.sp. Perennial, tufted, pale-green, the smooth culms 

 30-50 cm. tall, erect or slightly geniculate at the base: culm leaves three; 

 sheaths rather loose and inflated, shorter than the internodes, smooth; 

 blades flat, 6-12 cm. long, 2-6 mm. wide, acuminate, strongly scabrous 

 above, less so beneath; ligule scarious, 3-5 mm. long: spike usually well 

 exserted, pale and silvery, 2-7 cm. long, about 5 mm. thick, erect, straight 

 or somewhat flexuous: empty glumes 2-5 mm. long, nearly equal, strongly 

 ciliate on the keels, obtuse: flowering glume hyaline, 2-nerved, as long as 

 the empty glumes, obtuse, bearing from near the base a stout geniculate awn, 

 5 mm. long, scabrous above the bend. Common in wet places. Nearest A. 

 californicus Vasey. The type is Piper No. 1743, collected at Pullman, June 

 20, 1893. 



