Populus tremuloides is a deciduous tree native to cooler areas of North America, one of several species referred to by the common name aspen.

Populus tremuloides is the most widely distributed tree in North America, being found from Canada to central Mexico.

[4][6] It is the defining species of the aspen parkland biome in the Prairie Provinces of Canada and extreme northwest Minnesota.

Parallel vertical scars are tell-tale signs of elk, which strip off aspen bark with their front teeth.

Quaking aspen occurs across Canada in all provinces and territories, with the possible exception of regions of Nunavut north of the James Bay islands.

In the United States, it can be found as far north as the northern foothills of the Brooks Range in Alaska, where road margins and gravel pads provide islands of well-drained habitat in a region where soils are often waterlogged due to underlying permafrost.

[4] In the sagebrush steppe, aspens occur with chokecherry, serviceberry, and hawthorn, forming a habitable haven for animal life.

[11] Shrub-like dwarf clones exist in marginal environments too cold and dry to be hospitable to full-size trees, for example at the species' upper elevation limits in the White Mountains.

Even if pollinated, the small seeds (three million per pound) are only viable a short time as they lack a stored food source or a protective coating.

[16] The buds and bark supply food for snowshoe hares, moose, black bears, cottontail rabbits, porcupines, deer, grouse, and mountain beavers.

This increased dieback has been linked to multiple stressors, such as defoliation by the forest tent caterpillar (Malacosoma disstria), wood-boring beetles such as the poplar borer (Saperda calcarata) and the bronze poplar borer (Agrilus liragus), and fungal disturbances such as those by the Cytospora canker (Valsa sordida).

As a result, some aspen groves close to cattle or other grazing animals, such as deer or elk, have very few young trees and can be invaded by conifers, which are not typically browsed.

[23] On the other hand, the widespread decimation of conifer forests by the mountain pine beetle may provide increased opportunities for aspen groves to proliferate under the right conditions.

[26] Aspen bark contains a substance that was extracted by indigenous North Americans and European settlers of the western U.S. as a quinine substitute.

[16] Like other poplars, aspens make poor fuel wood, as they dry slowly, rot quickly, and do not give off much heat.

[27] Aspen wood is used for pulp products[7] (its main application in Canada) such as books, newsprint, and fine printing paper.