118 



GRASSES OF IOWA. 



Macbride), Steamboat Rock (Shimek). 



North America. Illinois, Wisconsin (La Crosse, Pammel), Min- 

 nesota, Iowa, Missouri (Eggert), Nebraska, Colorado and Wyoming 

 (Griffith). 



3. AKISTIDA LONGISETA. 



Aristida longiseta Steud. Syn. PI. Glum. 1: 420. 1855. Merrill. Circ. 

 U. S. Dept. Agrl. Div. Agros. 34: 3. 



Aristida fasciculata Nuttall. Thurb. Beal Grasses N. A. 2: 208. 1896. 



DESCRIPTION. 



Purple Aristida. A densely tufted, glaucous, glabrous perennial; 

 culms 4 to 18 inches (1-4 dm.) tall, erect, slender, smooth or rough, 

 usuallv with purplish setae and with numerous, involute basal leaves. 



Sheaths shorter than the 

 internodes, smooth or 

 slightly scabrous; ligule 

 short with a ciliate fringe ; 

 leaves 1 to $j, inches (2- 11 

 cm.) long, \ line ( 1 mm.) 

 wide, involute, at least 

 when dry, usually scab- 

 rous. Panicle few flow- 

 ered, exserted, the branches 

 solitary or two or three at 

 the lower nodes, ascend- 

 ing; spikelets rather large, 

 purplish, lower empty 

 glume one-nerved or some- 

 times with an obscure 

 additional nerve on each 

 side ; empty glumes un- 

 equal, the first shorter 

 than the flowering glume, 

 slightly scabrous on the 

 keel, acute or with a very 

 short, mucronate tip. 1 1 



Fig. 84. Aristida lonqiseta—a,, spikelet;b, flower-. , , , „' 



ing glume. (Div. Agros. 'u. s. Dept. Agrl.) mm. long; second glume 



much exceeding the flowering glume, about 20 mm. long, otherwise 

 much as the first; flowering glume 6 lines (12 mm.) long, including the 

 densely pubescent callus, which is about 1 mm. long, smooth below, 

 scabrous above. Setae nearly equal, scabrous, about 3 inches (7cm.) 

 long. July to September. 



