132 THE ESSENTIALS OF AGRICULTURE 



6. What are the three distinct dry-farming areas of the United States ? 



7. In general, what is the annual rainfall required in dry-farming areas? 

 How does this compare with the annual rainfall in your locality ? 



8. How does the manner in which the rainfall is distributed affect dry 

 farming ? How does evaporation affect dry farming ? 



9. Discuss the different methods for preparing the soil to absorb and 

 hold moisture. 



10. Compare the results of alternate cropping of wheat with the results 

 of continuous cropping. 



11. Why are certain crops best adapted to dry farming? 



REFERENCES 



DAVIDSON, J, B. Agricultural Engineering. Webb Publishing Company. 

 ELLIOTT, C. G. Practical Farm Drainage. John Wiley & Sons. 

 MACDONALD, WILLIAM. Dry Farming. The Century Co. 

 SHAW, THOMAS. Dry-Land Farming. The Pioneer Company, St. Paul, 



Minn. 

 SMYTHE, WILLIAM E. Conquest of Arid America. The Macmillan 



Company. 



WARING, G. E. Tile Drainage. Orange Judd Company. 

 WARING, G. E. Draining for Profit and for Health. Orange Judd Company. 

 WIDTSOE, J. A. The Principles of Irrigation Practice. The Macmillan 



Company. 



WIDTSOE, J. A. Dry Farming. The Macmillan Company. 

 Agriculture in the Central Part of the Semi-Arid Portion of the Great 



Plains, Farmers' Bulletin 215, Bureau of Plant Industry, United States 



Department of Agriculture. 

 Dry Farming in Relation to Rainfall and Evaporation, Farmers' Bulletin 



1 88, Bureau of Plant Industry, United States Department of Agriculture. 

 Dry Farming in the Great Basin, Farmers' 1 Bulletin 103, Bureau of Plant 



Industry, United States Department of Agriculture. 

 Water Requirements of Plants, Farmers' Bulletin 284, Bureau of Plant 



Industry, United States Department of Agriculture. 

 Tile Drainage on the Farm, Bulletin 524, United States Department 



of Agriculture. 

 Drainage of Farm Lands, Bulletin 187, United States Department of 



Agriculture. 

 Irrigation in Field and Garden, Bulletin 138, United States Department 



of Agriculture. 



