THE MEMPHIS SILT LOAM. 9 



The development of the type in a long, narrow belt extending from 

 the central United States almost to the Gulf of Mexico gives rise to 

 a wide variation in the climatic surroundings under which it is culti- 

 vated, and this factor of climatic influence modifies to a considerable 

 degree the crop adaptations of the soil in its different localities. In 

 the more northern regions the general farm crops, particularly corn, 

 winter wheat, oats, and grass, are well suited to the Memphis silt 

 loam. In the central regions, including Kentucky and western Ten- 

 nessee, tobacco is also grown to advantage, though to a very limited 

 extent, while cowpeas and even cotton are produced. From western 

 Tennessee southward the climatic surroundings are such that cotton 

 constitutes the principal money crop, and even corn is grown in sub- 

 ordinate acreage. With the exception of cowpeas for forage pur- 

 poses, and of local developments of market -gardening and trucking 

 crops, the more southern portions of the Memphis silt loam are de- 

 voted almost exclusively to the growing of cotton, with corn as a 

 supplementary crop. 



IMPROVEMENT IN SOIL EFFICIENCY. 



Protection from erosion is the prime necessity for the better devel- 

 opment of the Memphis silt loam. This may be accomplished in 

 a variety of ways, depending upon the declivity of surface slopes, 

 upon the amount and character of the annual rainfall, upon the 

 proximity of deep-cut drainage ways or of shallow stream valleys 

 and gullies, and to a considerable degree upon the selection of crops 

 made in the natural adjustment to climatic conditions. In the more 

 northern areas where the Memphis silt loam is developed, very little 

 attention to erosion problems is necessary beyond the production of 

 grass upon the more gentle slopes, and the occupation of the steeper 

 slopes by forest. Even the moderate slopes may be planted to 

 orchard fruits, provided a little care is taken to arrange the rows 

 according to the contours of the land. Such a use of this type has 

 been made to a considerable extent in one or two areas, and very 

 little difficulty from erosion has been experienced in such cases. 

 Farther south the adoption of contour farming, of terracing, of the 

 construction of brush dams to prevent the invasion of gullies upon 

 tilled land, the grassing of the steeper slopes, and the forestation of 

 declivities along the bluff are methods requisite for the prevention 

 of erosion. 



On the more gently sloping surfaces deeper plowing to form an 

 absorptive reservoir for rain water, the careful construction of water 

 furrows to prevent the too rapid off-flow of excess water, and the 

 adoption of a crop rotation which shall leave the 'surf ace of the land 

 occupied by cover crops during the winter months and by grass cover 

 during a portion of the rotation are all desirable methods for main- 

 100241 Cir. 3511 2 



