Douglas fir and aspen forest is a plant community or

vegetation type Vegetation classification is the process of classifying and mapping the vegetation over an area of the earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource management, resource and envi ...

of the mountains of the western United States, dominated by Douglas fir ('' Pseudotsuga menziesii'') and Quaking aspen (''

Populus tremuloides ''Populus tremuloides'' is a deciduous tree native to cooler areas of North America, one of several species referred to by the common name aspen. It is commonly called quaking aspen, trembling aspen, American aspen, mountain or golden aspen, tr ...

'').Spatial patterns of Douglas-fir and aspen forest expansion; Sankey, Temuulen Tsagaan; New Forests;Jan2008, Vol. 35 Issue 1, p45

References

Pseudotsuga Forests of the Rocky Mountains {{Forestry-stub