Canada, Great Lakes, inland W. USA
"Quaking aspen forests provide important breeding, foraging, and resting habitat for a variety of birds and mammals. Wildlife and livestock utilization of quaking aspen communities varies with species composition of the understory and relative age of the quaking aspen stand. Young stands generally provide the most browse. Quaking aspen crowns can grow out of reach of large ungulates in 6 to 8 years. Although many animals browse quaking aspen year-round, it is especially valuable during fall and winter, when protein levels are high relative to other browse species....
Wild and domestic ungulates use quaking aspen for summer shade, and quaking aspen provides some thermal cover for ungulates in winter . Seral quaking aspen communities provide excellent hiding cover for moose, elk, and deer. Deer use quaking aspen stands for fawning grounds in the West. Ungulates generally do not use quaking aspen much in winter. Perala reported that in the Great Lake States, pure quaking aspen stands provided white-tailed deer with relatively poor insulation and protection from winter winds compared to adjacent stands of conifers." 
"Mountain slopes covered by quaking aspen provide high yields of good-quality water. Quaking aspen intercepts less snow than conifers, so snowpack is often greater under quaking aspen.
Well-stocked quaking aspen stands provide excellent watershed protection. The trees, the shrub and herbaceous understories, and the litter of quaking aspen stands provide nearly 100 percent soil cover. Soil cover and the intermixture of herbaceous and woody roots protect soil except during very intense rains.
Quaking aspen is valued for its aesthetic qualities at all times of the year. The yellow, orange, and red foliage of autumn particularly enhances recreational value of quaking aspen sites.
Quaking aspen is widely used in ornamental landscaping." 
"Quaking aspen is one of the most important timber trees in the East. Its wood is used primarily for particleboard, especially waferboard and oriented strandboard, and for pulp. In the Great Lakes States, quaking aspen is the preferred species for making oriented strandboard. Quaking aspen fibers are well suited for making fine paper. Some quaking aspen is used for lumber. Quaking aspen lumber is used for making boxes, crates, pallets, and furniture. A small but growing volume is made into studs. Quaking aspen wood is little used in the West, except in Colorado, where it is used for pulp and particleboard. Specialty products from quaking aspen wood include excelsior, matchsticks, and tongue depressors. Quaking aspen pellets are used for fuel.
The wood of quaking aspen is light, soft, and straight grained. It has good dimensional stability and it turns, sands, and holds glue and paint well. It has relatively low strength, however, and is moderately low in shock resistance. Both sapwood and heartwood have low decay resistance and are difficult for preservatives to penetrate. Quaking aspen wood warps with conventional processing, but saw-dry-rip processing controls warping." 
 Howard, Janet L. 1996. Populus tremuloides. In: Fire Effects Information System,. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/poptre/all.html.