A typical stand of aspen trees is a large cluster of clones, that is, trees sprouting up from the roots of the mother tree. The aspen tree flowers early in the spring and produces small cones that will burst and send millions of seeds into the wind. However, aspen trees are almost entirely spread by suckers. After the 1988 fire in Yellowstone National Park the aspen seeds were found to be growing in burned out areas, noted as a rare event.
The aspens prefer cool, dry and sunny conditions, growing from 40 to 70 feet in height. The smooth, white trunk can grow to a diameter of two feet. The beauty of these white trunks against the deep, blue sky are evident in the late fall and winter when the colorful fall foliage has dropped to the ground.