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Important considerations in assessing these impacts are the natural 

 characteristics of the watersheds. Much of the Upper Yellowstone drainage 

 contains highly unstable soils derived from volcanic material and fine- 

 grained sedimentary rocks; loose alluvial soils also present water 

 erosion hazards (DHES, 1976). 



Forestry practices can easily aggravate these potentially erosive conditions 

 and such practices may necessarily be restricted in some areas. 



Mitigation measures should be applied on a basin-wide basis to adequately 

 deal with the identified problems. 



Effects of past and present harvest activities in the area should be care- 

 fully evaluated before any additional areas are committed to timber 

 harvesting or associated road construction (either private of USPS), 



In a coordinated basin-wide approach of forest! and management, further 

 aggravation of existing problems and creation of new problems will be 

 prevented. 



