Pando: Utah’s Cloned-aspen Giant

October 17, 2019



October 2019 Viewer's ChoicePhotographer: Ray Boren 
Summary Author: Ray Boren 

As motorists approach the south shore of Utah’s alpine Fish Lake (elevation 8,848 feet or 2,700 m), in Fishlake National Forest, they’re greeted by new signs that alert them to the fact that they are “Entering the Pando Aspen Clone.” The travelers have ventured into the heart of one of the biggest, and oldest, known organisms on Earth. It’s a grove of some 47,000 quaking aspen clones, all of which have sprouted from a shared ancient root system, and thus descend from the same original seed — the two ways aspen reproduce. Pando, Latin for I spread, is, by this description, a single 107-acre (43 hectares) plant.

Pando is especially glorious in autumn, as illustrated in the photographs here, taken on October 2, 2019. True to their name, the leaves of the quaking aspen (Populus tremuloides) were trembling in a light breeze and seemed to shimmer in the sunlight under a clear blue sky. The leaves are ending summer production of green-tinted chlorophyll, and revealing their carotenoid pigments, which manifest as yellows, golds, oranges and reds, before they drop away for winter.

Scientists first recognized Pando’s unusual size, unity and age in the 1970s, and recent genetic testing has proved the cloned grove to be one massive organism, the U.S. Department of Agriculture affirms. It’s been deemed at times the largest plant in the world and was featured on a 2006 U.S. postage stamp spotlighting 40 Wonders of America. Of course, other large cloned aspen forests — the most widespread tree species in North America — could be bigger, but candidates remain undiscovered.

Although Pando is estimated to have germinated about 80,000 years ago, during the Pleistocene ice age, its stands of trees, the eldest of which are over a century old, come and go. In fact, the ancient grove and its root system may be dying, perhaps withering away due to the scarcity of young stems, as older trees die. In hopes of saving Pando, sections have been fenced off by the U.S. Forest Service and research partners like Utah State University, as part of a recovery and regeneration project. Along with other strategies, the fences might give the fledgling aspens a chance to thrive — and to carry on a legendary tale of endurance.