250 THE rRAlllIE GRASSES. 



its growth, and convert it into dried bay, is not suffi- 

 ciently known for the different districts. It is probably 

 controlled more by absence of water in the soil, and 

 want of rain, than by temperature the heat being 

 sufficient for this purpose when the water wholly fails. 



Wislizenus, Emory, and Abert, met the smaller gram- 

 ma, called the buffalo grass, at 38 north latitude, and 

 by their references it might be inferred that this was 

 the northern border at that degree of longitude. But 

 Fremont found it at 40, on the same meridian, and 98 

 west longitude, and near the Platte or Nebraska River. 

 It probably extends still further northward, and over 

 much of this great plain to the Missouri. There are no 

 satisfactory notices of the grasses of this great region ; 

 but the inference is reasonable that it should range 

 nearly as far as subsistence is afforded to the immense 

 herds of buffalo occupying that area. The recent sur- 

 veys north of the Missouri were, however, unable to 

 find any considerable amount of it ; and Richardson was 

 also unable to find the buffalo grass on the Saskatcha- 

 wan, though at the time of his visit recent fires had 

 destroyed the growth of all kinds. He remarks a large 

 intermixture of carices with the festuca, and other true 

 grasses, on all the northern portions of the prairie 

 region. 



The new forms of valuable grasses found in this great 

 range in our interior deserve the greatest attention in 

 reference to their introduction in field cultivation. The 

 native species of the prairie region, east of the Missis- 

 sippi, probably cannot be cultivated they give way 

 too easily at the approach of cultivation, and those of 

 the dry prairies are rarely found in seed. The turf of 

 this prairie growth is very strong and enduring ; and 

 in the native state these are valuable grasses, well 

 adapted to the intermediate climates in which they 

 occur, where the humid and dry conditions pass into 

 each other by gradual transition. These range over 

 most of the country of the upper Missouri, as well as 

 on the prairies eastward. 



There is a large district in the United States deficient 



