22

ECONOMIC GEOLOGY.

SOILS.

The soils of the county are all fit for cultivation. The virgin soil is in most places of a fairly good grade, but those under cultivation are rapidly deteriorating, and some of them have already reached a stage which renders them unprofitable for the cultivation of cotton, the staple product of the county, and are nearly in the same condition for corn production, especially the upland gray sandy and light prairie soils.

This deterioration can readily be noticed. At first small spots appear in various portions of the field, upon which the cotton plant, never very vigorous, begins to get brown and shriveled, and finally dies. These spots may not at first include more space than is covered by two or three plants, but as the season passes they grow larger, until the area included by them forms a considerable portion of the ground under cultivation. With each succeeding cotton crop this area increases. While as yet in no place observed has corn failed to grow on these spots, this crop also shows a falling off from preceding years.

Physically there appears to be no difference between these unproductive areas and the surrounding portions of the land, but chemically the constitution of the two differ in many respects. The following analyses show the chemical as well as the physical conditions of the two. Both are taken from the same field and not very far apart. Nos. 1329 and 1330 show the cotton producing soil, and Nos. 1327 and 1328 the character of one of the areas in which the cotton dies:

The physical condition of these soils is shown by mechanical analyses to be: