LESSON LVII 

 DRY FARMING 



Farming in semiarid regions. In the eastern half 

 of the United States the rainfall of from twenty-five 

 to sixty inches is sufficient for successful agriculture 

 by common methods. In semiarid regions, where the 

 rainfall amounts to from fifteen to twenty-five inches, 

 the production of profitable crops is quite uncertain 

 under the ordinary farm practice. To raise crops 

 without irrigation in these regions requires special 

 methods of tillage and special kinds of crops. The 

 growing of drought-resistant crops by tillage methods 

 that enable the soil to gather and hold the largest pos- 

 sible amount of moisture is dry farming. 



Soil moisture. - - There are three ways by which the 

 soil loses the moisture it receives from rain and snow. 

 A large part of it sinks into the ground and passes away 

 by drainage, part of it comes to the surface and evap- 

 orates into the air, and another part is taken up by 

 the growing plants and transpired into the air from 

 the leaves. 



Methods of retaining soil moisture. --To secure and 

 retain the largest possible amount of soil moisture from 

 rain and snow, the following operations are carried on 

 in the dry-farming belt. 



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