Although absent from most of Texas, the southeast, and the middle Atlantic states,quaking aspen groves can be found in all of the northern and western states in the United States. The range extends through most of Canada, from Newfoundland to the Yukon, and north to the Brooks range of Alaska. On the other extreme, quaking aspen has found its way into the high mountains of Mexico as well. Generally found on sites that recieve large annual snowfalls, groves in the West may be found at elevations as low as 2000 feet in Alaska, and as high as 11,500 feet in the southern Rockies, while those in the north and east may grow at much lower elevations. At higher elevations, aspens are generally found on south-facing slopes, while at lower elevations they more frequently inhabit more sheltered sites.