THE BLUE-GRASSES 95 
The distribution of blue-grass south of the glacial 
dritt is exceedingly interesting. In this region it is 
confined to the magnesian limestone soils of the geo- 
logical area known as the Cambrian. A great tongue 
of this limestone soil extends southward from Cincin- 
nati, Ohio, into northern Kentucky, a distance of 
about one hundred and ten miles, and is nearly one 
hundred miles broad. This constitutes the famous 
‘‘ Blue-Grass Region ’’ of Kentucky. The geographical 
centre of this region is a point about twenty-two miles 
north of the City of Lexington, and it extends about 
twenty-five miles south of that city. It is in this re- 
gion that most of the blue-grass seed of the country is 
harvested. From this a narrow strip extends into 
Tennessee, and there spreads out and occupies the 
‘‘central basin’’ of that State. Blue-grass again ap- 
pears in the mountain valleys of eastern Tennessee and 
western Virginia, where it is an important pasture- 
grass. It appears more sparingly in the hill country 
of the western Carolinas, northern Georgia, and north- 
ern Alabama. Some blue-grass is also grown on the 
black, sticky prairie soils of northeastern Mississippi. 
The Cambrian soils above referred to are the only 
southern soils that at all resemble those of the region 
north of the Ohio River, and it is only on them that the 
type of farming prevalent in the North is found in the 
South. Aside from the exceptions just noted, blue- 
grass is confined rather stri@tly to the glacial drift of 
the Northern States. Its very general distribution 
over the drift area is supposed to be due to the lime, 
magnesia, and, perhaps, potash in these soils. Climatic 
conditions are also more favorable to blue-grass in the 
