As the days get shorter and the nights get cooler we notice the shift in color among the trees around us. If you live near aspen stands you might notice that a group of trees will change colors all at once. This is because aspens grow as a clonal colony from a single seedling. I am referring to the Quaking Aspen (Populous tremuloides) in this post although there are a number of aspen species found around the world. The Quaking Aspen is widely distributed throughout North America. It is one of the first tree species to colonize an area after a forest fire by sprouting new trees through it’s deeply buried root system.
These colonies can live for a surprisingly long time although individual trees die out (only to have a new tree sprout up from the extensive root system). The oldest known colony can be found in Fishlake National Forest in Utah. According to the US Forest Service this clone named Pando (Latin for “I Spread”) is about 80,000 years old. It spans 106 acres, consists of over 40,000 individual trees, and weighs over 14 million pounds. However, the Pando is beginning to show it’s age. A combination of insects, disease, drought, and human disturbance is compromising the health of this ancient tree. The Forest Service is actively trying to restore the Pando so that future generations can witness this biological marvel.