Aspen's Features Create Uniquely Biodiverse Environment

May 13, 2014

Utah’s new official tree, the aspen, may possibly be the largest of all state trees if you look at it like scientists do—as a clone colony, which can grow to weigh 13 million pounds.

The aspen tree grows in complex underground root systems that link clone trees together.
Credit United States Department of Agriculture Forest Service

The aspen trees you see above the ground are better thought of as stems of a much larger underground organism, according to Utah State University extension agent Jody Gale.

“Often in the fall as the aspen leaves change colors, you’ll be looking at a hillside and you’ll see one patch of aspen that’s maybe yellow and you’ll see a different patch that has a little more of an orange color to it,” said Gale. “What you are seeing are different organisms or different clones.”

Each of these stems lives 120 to 150 years, much less than trees found in evergreen forests. Gale says despite the shorter lifespan, aspen forests provide a uniquely biodiverse landscape.

“An evergreen forest that has pine and spruce and fir and a number of other evergreen-type trees in it is not very diverse as far as biology. Whereas if you’re in an aspen environment, you have a greater number of insects of all kinds, birds of all kinds, wildlife in general and all of the different animal and plant and insect species that we share the environment with,” said Gale.

Aspen forests have been on the decline due to a number of factors, allowing for the less diverse evergreen forests to encroach upon their traditional habitat. This is unfortunate for a number of reasons, says Gale, because beyond biodiversity, aspens allow for a more gradual melt of winter snows and tend to hold on to more water in their giant root systems.

Despite their new found fame, Gale says Utah residents should think twice before planting aspen in residential areas as they are not well suited for the warmer valleys or the insects found there.