IRRIGATION FARMING 



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On very level land, basins are formed by throwing 

 up ridges of soil. A basin may be a small one around 

 each tree in an orchard, or it may cover one or more 

 acres of a field. When the plants need water, it is 

 allowed to flow 

 into the basins 

 from the ditches 

 or laterals. This 

 method is called 

 basin irrigation. 

 In check irriga- 

 tion ridges of 

 soil are thrown 

 up across a field 

 to check and 

 guide the water 

 that flows over 

 the surface from 

 the lateral. This 

 method, called 

 check irrigation, 

 is a modification of flood irrigation. There are' several 

 modifications of each of these methods. 



Irrigation in ancient times. Irrigation farming has 

 been practiced since very ancient times. In Egypt, 

 thousands of years ago, there were irrigation works, 

 and the annual overflows of the Nile also irrigated large 

 areas in the river valley. In the southwestern part of 

 the United States, long before the discovery of America 



IRRIGATING FRUIT TREES 



