140 



Agrostideae 



Aristida 



~^0 



Map 245 



Aristida longespica Pon 



3. Aristida longespica Poir. (Aristida gracilis Ell.) Map 245. Infre- 

 quent to frequent, but plentiful where found, in the southern part of the 

 state. Usually abundant in hard, white clay soil in low, flat, fallow fields 

 and in habitats similar to those of the preceding species. Probably also 

 infrequent in the sandy areas of the northwestern part of the state, 

 although there are specimens only from Starke County. Our specimens 

 vary somewhat in the length of their awns, but I do not think the varia- 

 tion has any taxonomic value. 



N. H. to Mich., southw. to Fla. and Tex., especially on the Coastal Plain. 



4. Aristida intermedia Scribn. & Ball. Map 246. This species seems to 

 be local but abundant where it is found. I have seen acres of it in Newton 

 County in the old lake bed, and in Noble County it forms large colonies 

 on the former bottom of Tippecanoe Lake. Local in moist, sandy soil on 

 interdunal flats about Lake Michigan, in moist sandy, prairie habitats, 

 and on moist sandy borders of lakes. 



Ind. to Nebr., southw. to Miss, and Tex. 



5. Aristida purpurascens Poir. Map 247. Infrequent in very dry sand 

 in the northwestern part of the state and in a similar habitat in Knox 

 County. Its habitat is found in contiguous counties, and doubtless its 

 range will be extended. 



Mass. to Kans., southw. to Fla. and Tex. 



6. Aristida ramosissima Engelm. Map 248. This is an infrequent grass 

 of the southwestern counties in hard, white clay soil in abandoned and 

 fallow fields, on washed slopes, along clayey roadsides, and infrequently 

 in yellow clay soil. 



Ind. to Iowa, southw. to Tenn., La., and Tex. 



7. Aristida oligantha Michx. Prairie Three-awn Grass. Map 249. 

 Like the other species of the genus, this species is partial to a slightly acid 

 soil and is infrequent to frequent in the southern half of the state where 



