4 What the NATIONAL FORESTS Mean to the WATER USER 



industries and approximately twice as much as the output of precious metals. 

 California, the "Golden State," contributes annually nearly four times as 

 much wealth in crops as in precious metals. 



If the precipitation were as evenly distributed in the West as it is in the 

 East, there would not be the need for irrigation that now exists, and the main 

 purpose of the National Forests would be simply timber production. But 

 it is not evenly distributed, and that is where the trouble lies. Except for a 

 narrow strip along the Pacific coast from San Francisco north to the Canadian 

 line, the great bulk of the precipitation occurs in the mountains. Through- 

 out the Coast Ranges, the Cascades and Sierra Nevadas, and the Rocky 

 Mountains and Colorado Plateau the rain and snowfall is far greater than 

 in the intermediate valleys and plateaus. 



The result is that the majority of water users depend for their supply 

 on water that originates a considerable distance away. Some of the most 

 productive agricultural lands in the region receive hardly more than enough 

 precipitation to support a desert vegetation, while the evaporation is 

 correspondingly great. Greeley, Colo., Provo, Utah, Phoenix, Ariz., and 

 Fresno and Riverside, Cal., all of which are in the center of extremely 

 productive sections, have an annual precipitation of less than 15 inches 

 with an annual evaporation from a free water surface at least three or four 

 times as much. 



As a natural consequence of the difference in amount of precipitation 

 in the mountains and at the lower elevations, the former are generally 

 forested and the latter treeless. The National Forests, of course, are 

 located in the mountains, where the trees are. From the brush-covered 

 foothills of the San Jacinto and San Bernardino Mountains in southern 

 California to the magnificent Douglas fir forests of the Olympic Mountains 

 in northern Washington, and from the pinon and juniper stands of the 

 southern Rockies in New Mexico to the pine forests of the northern Rockies 

 in Montana and Idaho, the mountains and the National Forests coincide. 



The intimate relation that exists between the National Forests and 

 irrigated lands throughout the West is shown on the map (fig. i). 1 At 

 least 85 per cent, and very likely more, of the water used to irrigate these 



1 The irrigated areas shown on this map are not always drawn exactly to scale; nor is the 

 entire area shown as irrigated actually irrigated, any more than the entire area shown as 

 National Forest land is actually owned by the Federal Government. To have attempted to 

 show nonirrigated or privately owned lands within the exterior boundaries of irrigation projects 

 or National Forests would have been impossible on a map of this scale. 



