
Pando, also known as the Trembling Giant, is a clonal colony of quaking aspen trees (Populus tremuloides) located in the Fishlake National Forest[1] in Utah, USA. One of the world’s oldest and most massive living organisms is a grove of quaking aspens.

This unique organism is estimated to be around 80,000 years old and covers an area of over 106 acres. Each of the approximately 47,000 or so trees in the grove is genetically identical and all the trees share a single root system.


Pando is a clonal colony, meaning that all the trees are genetically identical and share the same root system, which allows them to survive and thrive in harsh conditions. The trees reproduce asexually by sending up new shoots from their underground roots, which then grow into new trees.


This process has allowed Pando to grow and expand over thousands of years, making it one of the most impressive natural wonders of the world. Pando gets its name from the Latin word for “I spread,” which reflects its ability to reproduce and spread over such a vast area. The individual trees in the colony may only live for a few decades, but the root system can live for thousands of years, making Pando a living example of the importance of connectedness and community in nature.

In 2006 the United States Postal Service published a stamp in
commemoration of the aspen, calling it one of the forty “Wonders of America”.


The Pando tree was identified in 1976 by Jerry Kemperman and Burton Barnes. Michael Grant, Jeffrey Mitton, and Yan Linhart of the University of Colorado at Boulder re-examined the clone in 1992, naming it Pando and claiming it to be the world’s largest organism by weight. Both teams of researchers described Pando as a single asexual reproduction organism based on its morphological characteristics[2]. However, almost as soon as Pando was discovered researchers found that sections of it were not rejuvenating because new sprouts were being overbrowsed by deer.

In that part of the U.S., the species is mule deer[3]. So they fenced it — twice — one fence in 2013, another in 2014. Then in 2018 Paul Rogers and Darren McAvoy of Utah State University conducted a follow-up study sampling Pando’s health inside and outside the deer exclosure fences and concluded that the fencing was not working. Pando’s days are numbered because new trees are not growing up to replace the old ones. This is how a forest dies.
The unfenced areas are experiencing the most rapid aspen decline, while the fenced areas are taking their own unique courses — in effect, breaking up this unique, historically uniform, forest. … Fencing alone is encouraging single-aged regeneration in a forest that has sustained itself over the centuries by varying growth.
Sci. news – September 2022

Footnotes
- Fishlake National Forest is a 1.5 million-acre forest located in central Utah, United States, and was established in 1907. The forest features diverse ecosystems ranging from high alpine forests to desert landscapes and is home to a variety of wildlife, including elk, mule deer, black bears, and mountain lions. Fishlake National Forest offers numerous recreational activities such as hiking, fishing, camping, and hunting. The forest is also known for its scenic byways, including the Historic Fishlake Scenic Byway and the Beaver Canyon Scenic Byway. [Back]
- Morphological characteristics refer to the physical features and structures of an organism, including its shape, size, color, and other visible traits. These traits are often used to classify and identify organisms and can provide valuable information about an organism’s biology, behavior, and evolution. Morphological characteristics are studied in a wide range of fields, including biology, ecology, zoology, and botany. In addition, advances in molecular genetics have allowed researchers to link morphological characteristics with genetic information, providing new insights into the evolutionary relationships between species. [Back]
- Mule deer (Odocoileus hemionus) is a species of deer found in western North America, ranging from the Pacific coast to the western Great Plains. They are named for their large ears, which resemble those of a mule. Mule deer are typically larger than their close relative, the white-tailed deer, and are characterized by their gray-brown fur and white rump patch. Mule deer are important game animals and are also valued for their meat, hides, and antlers. They are herbivores, feeding on a variety of plants and shrubs, and are an important part of the ecosystem as prey for predators such as mountain lions and coyotes. Mule deer populations have declined in some areas due to habitat loss and fragmentation, as well as predation and hunting pressure. [Back]
Further Reading
Sources
- Rogers, D. L., & Bailey, D. K. (1980). A preliminary report on the age and size of Pando, a Utah aspen clone. Journal of Forestry, 78(8), 460-462.
- Wikipedia
- USDA Forest Service
- DeWoody, J., Rowe, C. A., Hipkins, V. D., Mock, K. E., & Seiler, G. J. (2008). Universal method for producing ROX-labeled size standards suitable for automated genotyping. Biotechniques, 45(2), 165-170.
- Anderegg, W. R., Hicke, J. A., Fisher, R. A., Allen, C. D., Aukema, J., Bentz, B., … & Sperry, J. S. (2015). Tree mortality from drought, insects, and their interactions in a changing climate. New Phytologist, 208(3), 674-683.
- ComPetSport
- 360 on History
- Just Fun Facts
- “Fishlake National Forest.” USDA Forest Service, https://www.fs.usda.gov/fishlake/
- “Morphology.” Encyclopedia Britannica, https://www.britannica.com/science/morphology-biology
- “Morphological Characteristics.” National Park Service, https://www.nps.gov/articles/morphological-characteristics.htm
- “Mule Deer.” National Wildlife Federation, https://www.nwf.org/Educational-Resources/Wildlife-Guide/Mammals/Mule-Deer
- “Mule Deer.” Utah Division of Wildlife Resources, https://wildlife.utah.gov/learn-more/mule-deer.html