GRASSES OF IOWA. 



171 



DESCRIPTION. 



Thin Grass. A per- 

 ennial with weak, slen- 

 der, and mostly decum- 

 bent, leafy culms, 

 about 2 feet (5 dm.) 

 high. Internodes short. 

 Sheaths smooth, striate, 

 shorter than the inter- 

 nodes; ligule about 1 

 line (2 mm.) long; leaf 

 blade flat, thin, widely 

 spreading, about 1 line 

 (2 mm.) wide, 4 inches 

 (8 cm.) long, acute, 

 scabrous. Panicle ob- 

 long, about 6 inches 

 (12 cm.) in length; 

 primary branches in 

 clusters of two to five 

 at a node, branched at 

 or below the middle; 

 the branches or pedicels 

 all widely divergent. 

 Spikelets pale green, a 

 line or less long. Empty 

 glumes rather unequal, 

 lanceolate, very acute, 

 rather minutely scab- 

 rous on keels. Flower- 

 ing glume a little shorter than empty ones. Damp, shady places. May 

 to September. 



Fig. 121. Agrostis perennans—a, outer or sterile 

 glume; b, flower. (Div. of Agros. U. S. Dept. of Agrl. ) 



DISTRIBUTION". 



Iowa. Alt. Pleasant (Mills) ; Des Moines, Boone (Carver) ; 

 Ames (Burgess, Pammel) ; Steamboat Rock, 3 171, 3 J 68 and 3053 

 (Miss King) ; Ames (Hitchcock) ; Steamboat Rock, Pine Creek (Miss 

 King); Marshalltown (Pammel); Steamboat Rock (Shimek). 



North America. From Quebec, New England, south along the 



