284 IRRIGATION PRACTICE 



tain any well-planted pasture in a luxuriant condition 

 throughout the season. This is a wide limit, and it is 

 probable that the best quantity lies near 18 inches. 



Irrigated pastures should not be grazed in early spring 

 or immediately after an irrigation, when the soil is soft, 

 because the plants may then be materially injured. 

 Meadows and pastures should be frequently disked or 

 harrowed, so that the top soil may be kept in a somewhat 

 loose condition. Such treatment will diminish the quantity 

 of water required throughout the season. Under the 

 most favorable conditions, the constant tramping of 

 animals on pastures will compact the top soil and thereby 

 increase evaporation, decrease the rate of water penetra- 

 tion and increase the quantity of water required for the 

 growth of the plants. The key to pasture maintenance 

 seems to be the relatively frequent applications of small 

 quantities of water to prevent any period of excessive 

 dryness. 



REFERENCES 



BARK, DON H. Duty of Water; Investigations (1910-12). Ninth 

 Biennial Report, State Engineer of Idaho (1912). 



COBURN, F. D. The Book of Alfalfa. Orange Judd Company 

 (1902). 



EVANS, M. W. Timothy Production on Irrigated Lands in the 

 Northwestern States. United States Department of Agricul- 

 ture, Farmers' Bulletin No. 502 (1912). 



FORTIER, SAMUEL. Irrigation of Alfalfa. United States Department 

 of Agriculture, Farmers' Bulletin No. 375 (1909). 



MCLAUGHLIN, W. W., and MORGAN, E. R. Report on Irrigation 

 Investigations during 1905-06. Utah Experiment Station, 

 Bulletin No. 99 (1906). 



OLIN, W. H. American Irrigation-Farming. A. C. McClurg Com- 

 pany (1913). 



