4. Abies lasiocarpa/Xerophyl lum tenax h.t. (Sub alpine fir/beargrass) . 

 This is the dryest habitat type of the sub-alpine fir climax series 



and occupies the relatively steep and dry, south- and southwest-facing 

 slopes. Moderately heavy understory stands of beargrass (50 to 75 

 percent coverage) are present in all stands of this type examined. 

 Existing overstory stands on this habitat type contain a high percent- 

 age of mature to overmature sub-alpine fir, Engelmann spruce, lodge- 

 pole pine, and western larch. Whitebark pine and western white pine 

 are occasionally encountered. Productivity of these sites is generally 

 low due to a limiting moisture situation which exists during July and 

 August. 



5. Abies lasiocarpa/Menziesia ferruginea h.t. (Subalpine fir/fool's 

 huckleberry) . This habitat type, which is indicative of the cool and 

 moist sub alpine fir zone, is present only as isolated patches in small 

 saddles or flats along the main ridge. Plots examined within this habi- 

 tat type area contain high individual species coverage of fool's hucKle- 

 berry (75 to 95 percent) and mountain alder (Alnus sinuata) (25 to 50 

 percent) . Merchantable timber stands within this habitat type consist 

 of a high percentage of mature to overmature subalpine fir, Engelmann 

 spruce, western larch, western white pine, lodgepole pine and whitebark 

 pine. Productivity of this habitat type for timber production is above 

 average if brush control measures are employed to facilitate tree re- 

 generation. 



In connection with this proposed sale, a comprehensive timber inventory 

 was carried out only in those areas designated for harvest. 



D. Climate and Hydrology 



The sale area is located in a region characterized by high precipitation 

 and runoff; the majority of the precipitation comes in the form of snow. 

 Precipitation ranges from about 40 to more than 50 inches annually. Annual 

 runoff averages from 17 inches to more than 25 inches. 



The proposed sale area was examined by a forest hydrologist employed 

 by the Division of For^f'xy during the sale planning process. On the 

 basis of the average to good site index, the intensity of harvest, and 

 unit size and location, it was concluded that an increase in water yield 

 of 30 to 35 percent will result from the seed tree and shelterwood harvest 

 units; an approximate 40 percent increase will result from the clear cut 

 units and roads. This significant increase in total water yield will be 

 modified somewhat by the varied topographical aspects involved, which 

 will result in a spreading of the increased yield throughout the runoff 

 period. 



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