Mountain slopes and ridges occur in both the upland and alpine landscape settings and are typically 

 composed of dissected mountain slopes, glaciated mountain slopes, and glacially scoured ridge tops. 

 The geomorphic processes that occur on these areas include colluvial, fluvial and glacial, erosion or 

 deposition. Parent materials are volcanic ash overlying bedrock composed of argillites, siltites, 

 quartzites, and limestones. The vegetation is a mosaic of coniferous forest, mountain shrublands, and 

 mountain grasslands. 



This landform Is a combination of glacially scoured ridge tops and dissected mountain slopes (fluvial). 

 Glacially scoured ridge tops have been strongly modified by continental ice. The prominent features 

 are ridge tops and ridge noses with exposed bedrock. These areas have slopes that range from 10 to 

 45 percent. Soils on these landforms are shallow to moderately deep, are weak to moderately 

 developed with medium textures. Slope gradients range from 30 to 60 percent. Soils on these 

 landforms are moderately deep to deep, with weak to moderate development, and gravelly medium 

 textures. 



The dissected mountain slopes landform is moderate to strongly dissected by ephermal and perennial 

 streams that occupy narrow "v" shaped valleys, with the dominate stream pattems being dendritic or 

 sub-parallel. These streams are typically classified as A or Aa+ stream types with gradients from 4 to 

 10+ percent. They are characterized by straight (non sinuous) cascading reaches, with frequently 

 spaced pools. When they are flowing through bedrock and boulders (A1 and A2) they are very stable 

 with low sensitivity to increases in water yields, peak flows or sediment. The streams in the ridge tops 

 landform position occur at the heads of drainages and are typically ephermal or intermittent streams 

 associated with seeps and springs. 



The riparian vegetation is dominantly Abies lasiocarpa/Streptopus amplexifolius, Abies 

 lasiocarpa/Oplopanax horridium and PIcea/Comus stolonifera riparian habitat types. 



The nitrogen yield from this landform group is moderate and the phosphorus yield is low. These are no 

 sensitive soils in this landform group. 



Stream Types Found in Big Creek 



The stream channels and valley bottoms in the Big Creek basins represent the entire range of 

 variability, from narrow "v" shaped valleys with bedrock waterfalls to broad flat valley bottoms 

 meandering streams in unconfined valleys. These valley forms and stream shape represent different 

 sediment transport and deposition processes. In its uppermost reaches, the capacity of Big Creek to 

 transport sediments exceeds sediment supply, so erosion is more common than deposition. Where Big 

 Creek flattens and begins to meander, at approximately the lower edge of the northeast aspect ski 

 runs, the capacity to transport sediments about balances the amount of available sediments. Here a 

 small change in water volume determines whether erosion or deposition occurs. As the stream 

 gradient continues to flatten downstream, deposition is dominant over erosion, except when high peak 

 flows occur to erode upper channel banks and transport the sediment downstream. 



The Rosgen Stream Classification System provides a method for identifying streams according to 

 various stream types by morphological characteristics (Rosgen, 1988). These morphological 

 characteristics include such factors as channel gradient, sinuosity, width/depth ratio, dominant particle 

 size of bed and bank materials, entrenchment of channel and confinement of channel in valley. A 

 Rosgen Stream Type Classification (level -1) was developed for the Flathead National Forest in 1999 

 using digital elevation models (DEMs). The computer model will only reliably identify A, B, C, and E 

 stream types. After review of the computer generated map the only other stream type found in the Big 



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