10 SOILS OF THE EASTERN UNITED STATES. 



recession of the water or by unusually low stages in the overflow. 

 In the more northern sections the area annually devoted to crop pro- 

 duction is extremely variable, since the farmers can plant or sow their 

 crops upon the Wabash clay only in favorable seasons. Thus the 

 area of the Wabash clay occupied in any one season may be greatly 

 increased or decreased, depending upon the flood-water stages of those 

 rivers flowing through areas of the type. In general, however, at- 

 tempts have been made at cultivation of probably 20 to 25 per cent of 

 the total area of the type. The larger proportion of this arable land 

 lies in the more southern States, particularly in Louisiana and in 

 Mississippi, where the levee systems are most complete. It is in these 

 States that the farm and plantation dwellings and the dwellings for 

 the tenants and hands employed upon the plantations are built within 

 the area of the alluvial bottoms. In practically all of the more 

 northern areas the type is unoccupied as a place of residence, or even 

 for the storage of crops, because of the danger from overflows. Even 

 in the leveed districts occasional overflows drive the inhabitants to 

 adjoining uplands until the waters have subsided. 



Increased areas of the Wabash clay may be occupied for agri- 

 cultural purposes through the formation of drainage or levee districts, 

 or through the united efforts of those farmers who own property in 

 any particular stretch of bottom land. It is usually only through 

 some such cooperative method that particular areas of the type may 

 be reclaimed. The heavy yields secured from this and the associated 

 types of the alluvial bottoms frequently justify an expense for the 

 establishment and maintenance of engineering works which would 

 not be justified for the improvement of upland soils. Thus there 

 remain thousands of acres of the Wabash clay and its chief associate, 

 the Wabash silt loam, awaiting a sufficient demand for land and the 

 proper organization and application of capital to become valuable 

 agricultural territory. 



CROP ADAPTATIONS. 



The crop adaptations of the Wabash clay vary with the climatic 

 conditions of the different areas. In all of the Northern States corn 

 constitutes the staple crop upon those areas which are tilled. Wher- 

 ever protection from overflow and proper drainage are obtained the 

 corn yields are heavy. In certain areas yields ranging from 40 to 75 

 bushels per acre are reported as the customary crop in years wlien 

 the corn fields are not destroyed or injured by overflow. In many 

 such areas corn has been raised from 10 to 20 years in succession upon 

 the same land without appreciable diminution in the yield except 

 through accident. In nearly all areas where corn has been planted 

 upon the type, minimum yields are reported in excess of 30 to 35 

 bushels, while maximum yields reach the unusually high figure of 60 

 to 75 bushels. Local drainage and the seasonal precipitation may 

 cause wide variations between these extremes. It would be difficult 



