A NATIONAL PLAN FOE AMERICAN FORESTRY 



WATER CONSERVATION 



589 



" Securing favorable conditions of water flows" was one of the two 

 major purposes of the national forests as stated in the act providing 

 for their creation, and for the enactment of the Weeks' law provision 

 for purchasing national-forest lands on the headwaters of navigable 

 streams. It has been one of the controlling aims in setting up pro- 



FIGURE 3. Virtually every major stream west of the Great Plains, and most of the minor ones, head in 

 a national forest and supply a large part of the water for the great irrigated land areas. 



visions for and restrictions on the use of national-forest resources and 

 in cultural operations relating to timber and forage. 



Virtually every major stream west of the Great Plains, and most 

 of the minor ones, head in a national forest. The western national 

 forests contains a large part of the most important western water 

 supply area. From these watersheds flows water which is the indis- 

 pensable basis for the rich irrigated farm and orchard developments 

 found in practically every Western State. Figure 3 shows the location 

 of the national forests with reference to irrigated lands. Except for 



