Aspen numbers are declining in the Bighorns. They have been for decades. Though there aren’t a lot of studies that provide the concrete numbers behind the decline, it’s enough of a decline that it’s visually obvious for many who’ve spent years working and recreating in the area.
That decline is concerning for foresters and biologists because aspen are a keystone and pioneer species. They provide wildlife habitat, and produce forage, help maintain water quality, provide recreational sites and add variety to the viewshed.
Source: Where have all the aspen gone?