THE .CECIL CLAY. 9 



Southward from this section in Virginia and northern North Caro- 

 lina the yields decline, until 15 to 25 bushels per acre represents 

 the ordinary production. Thence to the southern limits of the type 

 in central Alabama the corn yields rapidly 'decrease to an average 

 varying from 8 to 15 bushels per acre. This wide diversity in the 

 yield is due not so much to difference in climatic environment as 

 it is to differences in the efficiency of management of the soil itself, 

 particularly in the prevention of soil erosion. The yields in the 

 more southern regions are practically those which can be obtained 

 from the unskilled tillage of bare subsoils, since the surface soil 

 is annually washing away, and only the surface 2 or 3 inches of 

 material has been weathered out and mingled with organic matter 

 to furnish a complete soil. In these more southern locations corn 

 is not considered to be as well suited to production upon the Cecil 

 clay as is cotton. The difficulty of working the land sufficiently with 

 the light equipment used in cotton farming gives rise to shallow 

 plowing, to plow tillage instead of cultivation, and to continual bodily 

 losses of the surface soil, which reduce not only the yields of corn but 

 also of other crops. Under this partially efficient tillage the surface 

 soil in the cornfields, particularly, becomes baked and clodded and the 

 large moisture supply demanded by the heavy and rapidly growing 

 crop of corn can not be maintained. 



The Cecil clay in all of its northern occurrences is universally 

 used for the production of wheat. This is the principal small-grain 

 crop produced upon the type. The yields in Pennsylvania, Mary- 

 land, and some portions of Virginia are excellent, ranging from 

 15 to 30 bushels per acre, depending largely upon the previous treat- 

 ment of the land and upon the care with which it has been prepared 

 for the crop. In fact the Cecil clay constitutes one of the best wheat 

 soils east of the Allegheny Mountains, and only the Hagerstown 

 loam of the Limestone Valleys can normally compete with this type. 

 In the Middle Atlantic States, including North and South Carolina, 

 wheat is an important crop upon the Cecil clay, and yields range 

 from 10 to 20 bushels per acre. This latitude marks about the 

 southern limit of profitable wheat production upon any soil type 

 .except at high altitudes. The yields upon the Cecil clay may there- 

 fore be considered as unusually high under the attendant climatic 

 circumstances. Southward in Georgia and Alabama the yields are 

 usually much lower, ranging from 5 to 12 bushels per acre, and 

 wheat is not so generally sown as farther north. 



With the proper care of the soil and with the use of organic ma- 

 nures for fertilizers, the wheat yield even in the most southern loca- 

 tions where the crop is produced upon the Cecil clay might be ma- 

 terially improved. 



