Cascade Subalpine Forest Zone Complex
A group of zones marked by heavy snow flanks the Cascades and Olympics and extends into British Columbia. This group includes the Pacific Silver Fir Zone marked by Abies amabilis. At higher elevations, silver fir gives way to a more stunted forest of mountain hemlock (Tsuga mertensiana) and subalpine fir (Abies lasiocarpa) and forms a parklike pattern of open meadow and forest stringers. In areas of volcanic ash or areas recently disturbed by fire, even-aged stands of lodgepole pine (Pinus contorta var. murrayana) prevail. In southern Oregon, the zones bear close relationship to the California red fir forest.