WHAT WATER DOES IN SOILS 37 



This is true even of the sandy surface of the Mojave and 

 Colorado deserts in California, in some parts of which almost 

 no rain falls. The lower part of the Colorado desert (the 

 "Imperial" country) is being made by irrigation to give as 

 good crops as the Land of Goshen in Egypt. 



FIG. 16. Building an irrigation dam in Arizona. When finished, the 

 Roosevelt dam will be 284 feet high and able to hold water enough to^ 

 cover 1,300,000 acres a foot deep. 



It is only where the desert lands are stony or salty that 

 they are sometimes impossible to cultivate. This happens 

 in parts of Utah west of Great Salt Lake, and adjoining parts 

 of Nevada, where the ground is covered with salty crusts 

 too heavy to be washed out. 



In most deserts, then, it is possible to get good crops if 

 there is enough irrigation water and it is rightly handled. 



