Environmental Description:  Stands typically occupy moderate to steep upper mountain slopes and are often contiguous with the lower-elevation Abies amabilis - Tsuga heterophylla forests and higher subalpine Tsuga mertensiana and Callitropsis nootkatensis forests. This alliances occurs in the subalpine in the Cascades, extending from approximately 1200 to 1500 m in elevation. The climate is cool and wet with total annual precipitation totals generally exceeding 200 cm and deep (1-3 m) snow accumulations. A consistent winter snowpack of moderate duration along with frequent winter storms (snow on snow events) are driving factors in the occurrence of these forests. Podzolization is the dominant soil development process, and organic soil layers are generally well-developed. This alliance typically occurs in subalpine habitats, but may occur in slightly lower montane environments, such as slope benches or canyon bottoms, which are prone to cold-air drainage. This conifer forest alliance occurs in upper montane and subalpine habitats of the Pacific Northwest.