HOW TO CARE FOR SOIL 



3 2 7 



tain streams to hold back the water during wet seasons 

 or when the snow on the mountains melts. This con- 

 trolled water is usually permitted to flow through canals 

 to the farming lands. 

 Each farmer has one 

 or more small canals 

 running through his 

 farm and branch 

 canals to his various 

 fields. From the 

 smallest canals the 

 water is permitted 

 to flow out between 

 the rows of trees or 

 rows of crops that 

 may be growing. 

 The water is con- 

 trolled by opening 

 and closing flood- 

 gates of the branch 

 canals. Water is 

 sometimes allowed 

 to flow over the soil 

 when the crops need 

 it. Since the crops can be given water at the time when 

 it is needed, larger crops can be grown than in many 

 unirrigated districts where the crops have to depend upon 

 rain for water. For this reason it is a good investment 

 to spend money for irrigation. Even in the middle states 

 some progressive farmers have a system of watering their 

 vegetables and small fruits during long dry periods. 

 Berries while getting ripe need a great amount of water, 

 and often the crop can be doubled by having a small irri- 



IRRIGATION PROJECTS OF THE U. S. 

 GOVERNMENT 



Sites of dams and reservoirs. 



