The world’s largest living organism, Pando, dying in Utah

Pando, the world's largest organism, above Scenic Byway U-25, Utah, date not specified | Photo by J Zapell, St. George News

ST. GEORGE— Pando, an aspen clone located in Fishlake National Forest in central Utah, spreads across 106 acres, weighs approximately 13 million pounds and is likely thousands of years old. It is the largest living organism in the world. And it’s dying.

Pando, the world’s largest organism, Fishlake National Forest, date not specified | Photo courtesy of U.S. Forest Service, St. George News

According to the USDA Forest Service, an aspen forest is actually just one tree. The tree reproduces when shoots sprout from its roots and grow into a many genetically identical trees, resulting in an aspen “clone.”

Pando – which is Latin for “I spread” – is now starting to die from within. Most of the trees in the clone are older trees and reaching the end of their 150-year life. This cycle is natural, but what concerns ecologists is the lack of younger trees coming up to take their place.

Paul Rogers, adjunct associate professor at Utah State University and director of the Western Aspen Alliance, along with USU Extension assistant professor Darren McAvoy, recently published a research article discussing Pando’s ecosystem and the root cause of its decline: mule deer.

Well, kind of. 

The issue is not that Pando has ceased to make new shoots but that the mule deer browsing in the area tend to eat the young, nutritious aspen sprouts, preventing new trees from growing.

In addition, with each tree that dies and isn’t replaced, Pando loses more of the leaves it needs for photosynthesis and therefore the energy to produce enough new trees.

“The whole system starts to run out of fuel basically,” Rogers told St. George News.

The clone is not being reduced in acreage; it is simply thinning throughout. The decline first started to become noticeable in the 1960s and 1970s, and Rogers projects that over the next 10-20 years Pando’s system could collapse and be greatly reduced in size.

Rogers blames the problem not on the mule deer themselves but on human decisions when it comes to wildlife management.

Humans regulate deer a lot more than we think,” he said. “They’re not just wild roaming creatures.”

Cattle grazing in the area is also an issue, but they are making a much smaller impact on the clone than the deer.

An image showing the size and location of Pando, Fishlake National Forest, date not specified | Image courtesy of U.S. Forest Service, St. George News

Hunting is not permitted in the recreational area due to safety concerns with having roads, houses and a campground nearby. Because of this, the deer are seeking refuge there, resulting in an increased population in the area.

“The root cause is really humans and human decisions,” Rogers said.

Pando is not the only clone to be affected. Around the West, particularly around Southern Utah, Colorado, northern Arizona and New Mexico, elk eat aspen saplings resulting in a similar issue.  

Preserving aspen forests is not only good for the trees, but it also supports hundreds of species that inhabit them. In his article, Rogers discussed this concept of “megaconservation.” Instead of focusing on saving one species at a time, by preserving aspens they can help a lot of the species dependent on them at the same time.

Since his study, Rogers has begun working with the U.S. Forest Service and the Utah Division of Wildlife Services to make suggestions on how to best preserve Pando.

Part of the Pando clone of aspen trees all sourcing from one root system, Fishlake National Forest, Utah, date not specified | Photo by J Zapell courtesy of the U.S. Forest Service, St. George News

Steps to take include increasing education about Pando so that people know what it is, where it’s located and how they can help through either citizen science or donations. He also wants to work with local cattle ranchers to keep the animals out of the grove for a few years to allow Pando a chance to recover.

However, the number one thing they could do would be to reduce the deer population in the area, he said – specifically the 20-30 deer that are constantly browsing in the same place.

They are working to put up additional fences around the grove to keep the animals out. Even though over half of Pando is unfenced – and deer have found a way to get past some of the fences that are in place – the areas that have been successful at keeping animals out are doing very well.

One particular area that was fenced off in 2013 has trees that have grown to be 12-15 feet tall in five years.

It’s amazing that it’s been trying to sprout all this time, but all it needed was some protection of a fence,” Rogers said, but he added that while the fences have seen some success, it is only a temporary solution.

“It’s like putting a Band-Aid on a wound. The location is pretty sick, and we can do something to kind of give us a little more time and to stop the bleeding a little, but that’s a short-term solution,” he said. “It doesn’t address the longer-term solution.”

Part of the long-term solution is to reduce the deer population in a way that doesn’t compromise safety like hunting would. They also need to do a better job of coordinating management between wildlife and the forests they inhabit, Rogers said. In the Western U.S., the federal government manages the lands while the states manage the wildlife, and Rogers thinks they could do a better job of preservation by working together.

Funding for these projects has also been an issue. The government has yet to budget to fund preservation efforts for Pando.

“There will be a future of Pando; it just may be less than a fifth of the size that it is right now, the world’s largest living organism,” Rogers said. “It will quite rapidly recover if we have the will to fund it.”

Email: [email protected]

Twitter:  @STGnews | @MikaylaShoup

Copyright St. George News, LLC, 2018, all rights reserved.

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  • Craig October 24, 2018 at 12:42 pm

    I tire of those who think wildlife management, including hunting, is somehow horrible.

    I also hate overregulstion because the government controls too much now, especially the federal government.

    • Dougie October 24, 2018 at 10:55 pm

      the answer is wolves but the ranchers won’t allow it… this will be a cow pasture soon..

  • tazzman October 24, 2018 at 2:33 pm

    Just give out limited permit muley hunts in the area and construct more fencing around all of Pando. I’ve been and visited it. It’s a fascinating thing. Needs to be protected.

  • DRT October 24, 2018 at 6:32 pm

    Couple of wolves would take care of those deer…

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