The western white pine type is the most important forest unit over large areas of rough uplands in northern Idaho and adjacent portions of eastern Washington and western Montana. It occupies throughout this region the cooler, moister sites between elevations of 2,000 and 5,500 feet, reaching its best development in northern Idaho between the international boundary and the Lochsa River (10). The type is distinguished by its luxuriant growth and great complexity and characterized by the presence of western white pine (Pinus montícola D. Don) in association with a large number of other species, principally western red cedar (Thuja vlicata D. Don), western hemlock (Tsuga heterophylla (Raf.) Sarg.), lowland white fir (Abies grandis Lindl.), western larch (Larix occidentalis Nutt.), and Douglas fir (Pseudotsuga taxifolia (Lam.) Britt.).