Aspens are widely distributed throughout North America, preferring cold regions with cool summers; they grow at higher altitudes in warmer southern areas. One of the most common varieties is Trembling or Quaking Aspen, which are found throughout Canada and the United States apart from the Gulf Coast states.
Trembling Aspens are slender trees (20-80 ft tall) with heart-shaped leaves that turn yellow in the fall. The leaf stem is flat and set at a 90-degree angle to the leaf, causing them to tremble in even a gentle breeze. They have greenish-white bark with dark ridges on older trees. They often grow alongside Balsam Poplars and Birches.
Bigtooth Aspens (also known as Large-toothed Aspens) can be found in British Columbia and throughout eastern North America from Manitoba south to the Atlantic coast and as far south as Tennessee and North Carolina. Like Trembling Aspens, their leaves flutter in the wind, but the leaves are more egg-shaped with large, blunt teeth. Bigtooth Aspens send up root suckers, but their colonies are much smaller than those of Trembling Aspens. Their bark is a darker colour and the leaves can take on an orange-red tinge in the fall.
Aspen leaves and flower buds are an important source of food for Ruffed Grouse, while Deer (Mule Deer, White-tailed Deer) and Moose enjoy munching on the suckers. Beavers eat all parts of the tree.
Could it be? Cottonwoods and Balsam Poplars resemble Aspens as they are members of the same family. All of them release loose cottony seeds in late spring. Both Cottonwoods and Trembling Aspens have triangular or heart-shaped leaves, but Cottonwoods are usually taller and their leaves are slightly serrated. Balsam Poplars have oval or spear-shaped leaves.
Did you know? Trembling Aspens' roots send up shoots or suckers to form large stands of up to 100 acres of identical trees or clones. Individual trunks die, but the roots can live on for hundreds or even thousands of years.
