6 



MISC. CIECULAE, 4 7, U. S. DEPT. OF AGRICULTURE 



the total value of the land at present, or about one-half billion ^ 

 dollars. About 20,000,000 acres of the intermountain region is semi- W 

 barren and 154,000,000 acres, or 84 per cent, is valuable for its 

 native crops of timber and forage. 



VALUE OF WATEESHED PEOTECTION AS A FLOOD PKE\T:NTIVE 



The effect of watershed protection on floods is shown by an experi- 

 ence which the town of Manti, in central Utah, passed through about 

 1904 or 1905, when the watershed had been subjected to overgrazing 

 and fires. Floods were extremely frequent and destructive, rushing 

 out of the canyon above the town and doing great damage not only 

 to the town itself but also to the fertile fields located on the alluvial 

 fan at the mouth of the canyon. Damage estimated as high as 

 $125,000 was done in a few years. Conditions got so bad that some 

 of the more pessimistic talked seriously of moving awaj^ and aban- 

 doning the town, because they believed that it was destined to be 



^ 



Figure 2. — Behind the Arrowrock dam on the Boise River, Idaho, 

 rises on national-forest land 



The Boise River 



forever subject to destructive floods and that prosperity could never 

 exist there. After the creation of the Manti National Forest, in 

 1904, the watershed was carefully protected from fires, overgrazing, 

 and other destructive use. As a result Manti Canyon is singularly 

 free from floods at the present time. The water flow is even, the 

 town is prosperous. 



City Creek, which discharges out of a rough and precipitous 

 canyon into the very heart of Salt Lake City, has been protected 

 for many ^^ears from all forms of use as a precautionary measure. 

 In 1923 this canyon was undoubtedly subject to as heavy a rainfall 

 as Farmington Canyon, a short distance north, from which issued 

 a destructive flood. If such a flood had come out of City Creek 

 the property loss would have been enormous, but the stream rose 

 only about 4 inches. Watershed protection has a very real value 

 in dollars and cents. 



