6 SOILS OF THE EASTERN UNITED STATES. 



too wet nor too dry. If the ground is plowed when there is too 

 great a proportion of moisture present in the surface soil the fur- 

 row turns over in a long shining slice of compacted clay, which it 

 is practically impossible to harrow and cultivate into condition for 

 the seeding or planting of crops. Great difficulty is also experienced 

 in turning over the soil in this condition, because of the adhesion of 

 clay to the surface of the moldboard. On the other hand, if the sur- 

 face soil is permitted to become too thoroughly dry before plowing 

 is attempted, the surface is merely broken into a succession of hard, 

 compacted lumps, which no harrowing or rolling is capable of crush- 

 ing sufficiently to form a granular seed bed . in good tilth for the 

 planting of the crop. Between these two extremes, however, there is 

 a considerable range of moisture content for the surface soil within 

 which tillage operations are fairly easy and the results obtained are 

 satisfactory for the planting of the crop. When property plowed 

 and prepared, the surface soil rolls over in a friable, well-granulated 

 furrow, which requires little additional preparation. It is this char- 

 acteristic granulation, natural in some cases, induced by proper 

 handling in other cases, which gives the soil its popular name of 

 " buckshot land " and which renders it particularly valuable when in 

 this condition for the production of certain crops. 



In addition to this textural and structural limitation upon the 

 preparation and use of the soil, its utility for crop production is de- 

 cidedly limited by the time and frequency of inundations. Even in 

 areas which are thoroughly protected by levees along the principal 

 streams, the freshet waters from included tributary streams not infre- 

 quently rise over the lower lying areas of the Wabash clay to a depth 

 of 2 or 3 feet, remaining at such a stage long past the proper period 

 for the planting of the crop. 



Even after the overflow waters have subsided, some time is neces- 

 sary to permit the proper drying out of the surface soil, for tillage 

 operations must be undertaken when the soil contains the right 

 quantity of moisture to render these easy and effective. Moreover, 

 throughout a considerable proportion of the total area of the type 

 the water table, or zone of permanent saturation of the subsoil, is 

 near to the surface at all times throughout the growing season, and 

 any taprooted crops are injured or their production is prevented by 

 this condition. 



Thus, through its inherent properties, through its liability to over- 

 flow, and through its defective subsoil drainage the agricultural 

 occupation of the Wabash clay is restricted to such areas as are in 

 the best natural mechanical condition, as are reasonably protected 

 from unseasonable overflow, and as are provided either with natural 

 or artificial subsoil drainage. 



