FARM DRAINAGE AND IRRIGATION 777 



in the accumulation of alkali salts. In time, the concentration will pre- 

 vent the growth of crops. This can usually be avoided by greater care in 

 irrigating. Where conditions are such that it cannot be avoided in this 

 way, under-drainage should be installed. The alkali may now be washed 

 out of the soil through the underdrains, by flooding the surface with fresh 

 water. The use of alkali waters also stocks the soil with alkali salts. The 

 use of such water should be avoided as far as possible, or the difficulty 

 overcome by drainage and flooding as above mentioned. 



REFERENCES 



"Practical Farm Drainage." Elliott. 

 "Principles of Irrigation Practice." Widtsoe. 

 "Irrigation and Drainage." King. 

 "Irrigation Institutions." Mead. 

 "Practical Irrigation." Bowie. 

 "Irrigation." Newell. 

 "American Irrigation Farming." Olin. 

 Utah Expt. Station Bulletins: 



115. "The Movement of Water in Irrigation." 



118. "Method of Increasing Crop Producing Power of Water." 

 U. S. Dept. of Agriculture, O. E. S. Bulletins: _ 



177. "Evaporation Losses in Irrigation and Water Requirements of Crops." 



248. "Evaporation from Irrigation Soils." 

 Farmers' Bulletins, U. S. Dept. of Agriculture: 



373. "Irrigation of Alfalfa." 



371. "Drainage of Irrigated Lands." 



392. "Irrigation of Sugar Beets." 



394. "Use of Windmills in Irrigation." 



399. "Irrigation of Grain." 



404. "Irrigation of Orchards." 



524. "Drainage on the Farm." 



673. "Irrigation Practice in Rice Growing." 



698. "Trenching Machinery Used for the Construction of Trenches for the 

 Drains." 



