(8) Clearcutting in large blocks, (8) Protect open and green 

 overgrazing, and erosion destroy space with better planning and 

 natural beauty. land management. 



(9) Wildlife habitat is being lost (9) Preserve adequate waterfowl, 

 to agricultural, residential, indus- big game, upland, and other wild- 

 trial, and transportation encroach- life habitat. 



ment on riparian, forest fringe, 

 and wetland areas. 



Information on the whole study area is summarized within either economic 

 or hydrologic boundaries that best represent the total basin. Some infor- 

 mation is further summarized by three economic or three hydrologic sub- 

 areas: the Upper Clark Fork, the Lower Clark Fork, and the Flathead as 

 shown by map III-l. 



Physical Dimensions of the Basin 



The Clark Fork of the Columbia River Basin in Montana is 13.8 million 



acres in size, constituting about 8.3 percent of the total area of the 



Columbia River drainage and providing about 8.8 percent of its average 

 annual flow. 



The basin climate varies from humid alpine with over 100 inches of annual 

 precipitation to semiarid with less than 10 inches of annual 

 precipitation. Short growing seasons and cool temperatures during the 

 growing seasons, combined with soil and water limitations, effectively 

 restrict the types of crops and yields that can be produced in the area. 



The basin contains a wide variety of mineral deposits. Copper is the 

 single most important metal ore in Montana and over 99 percent of the 

 State's production comes from the Butte District. The basin has substan- 

 tial deposits of iron, lead zinc, tungsten, and manganese ores. 

 Considerable amounts of gold, silver, arsenic, and bismuth are available 

 as byproducts either from the copper mining at Butte or the smelting at 

 Anaconda. Other minerals are phosphate, mica, silica, barite. The most 

 important gems occurring in the basin are sapphires. Several small 

 deposits of coal and uranium ores are known and considerable exploration 

 is underway for oil and natural gas. 



The topography of the basin consists of steep mountain slopes and flat 

 river valleys with some well-defined terraces, but relatively few foot- 

 hills or prairie expanses. Most of the soils in the basin were developed 

 on mountain slopes under conifer forests and most of the basin had hard 

 rock materials rather than shales as parent materials. As a result, 

 there are larger acreages of coarser textured soils than of clays. As a 

 result of this, and man's activities, the basin lands are covered in the 

 following ways: 



