Vast Aspen Grove Pando Slowly Dies from Grazing Wildlife

A scientist is exploring the possibility of saving Pando, Utah's famous aspen grove and the largest living thing on Earth.

Pando is a huge aspen grove in south-central Utah. It is a single organism with 47,000 clonal stems, all connected by a single root structure.

Quaking aspens often reproduce by cloning with white stems and shimmering leaves that sprout from a single massive root system.

A single aspen clone often covers less than an acre. Pando, however, covers 106 acres. There are 440 stems per acre, averaging about one every 10 feet.

Furthermore, Pando stands on thousands of feet of volcanic rock.

In 2006, the aspen was featured on the postage stamp. Utah declared the quaking aspen an official state tree in 2014.

The Life Cycle of Quaking Aspens

Pando is considered the heaviest above-ground living thing on earth.

The entire aspen grove weighs at least 13 million pounds, three times more than the largest single tree on the planet, General Sherman, the giant sequoia in California.

Pando's weight is roughly comparable to that of 35 blue whales and 1000 elephants.

Each trunk of the grove lives between 85 and 130 years. Each time a trunk dies, new green shoots grow. However, the shoots are eaten by deer and cattle.

Paul Rogers, professor of ecology at Utah State University and director of the Western Aspen Alliance, has studied Pando and found that more stems die than grow back.

The conclusion was a result of 72 years of aerial photography he reviewed in 2018 along with the first comprehensive analysis of the forest.

His new 2021 inventory has not yet been peer-reviewed but shows a greater excess of mortality for Aspen Grove.

Some scientists claimed Pando was 80,000 years old, while others claimed Pando was 1 million years old. Rogers, however, pointed out that it is probably only a few thousand years younger than the last ice age, which ended about 12,000 years ago.

Rogers pointed out that there is a subtle change in Pando's ecosystem. Predators, such as wolves, bears, and pumas have been eradicated and cattle grazing has been allowed on the forest lands.

This change threatens the existence of Pando. Rogers explained that the forest is getting older, but the next generation is not surviving.

Also Read: Tree Survival Strategy: New Study Sheds Light on How Forest Ecosystems Survive Damaging Winds 

Pando's Health Problems

This is not the first time that Pando's health problems have been noticed.

Burton Barnes, a scientist from the University of Michigan, studied the forest in the mid-1970s. He walked through the forest and compared the leaves of neighboring trees to distinguish between stems that came from a single system.

Other scientists took DNA samples from 209 tribes across Pando decades later, showing Barnes was right.

The U.S. Forest Service cleared two small areas in the 1980s as part of an experiment, and nothing grew back.

Another area was cleared and fenced in 1992. The latter portion is now densely overgrown with trees about 5 inches in diameter, all about 35 feet tall.

In 2018, Rogers and a colleague were finally able to diagnose Pando's ailment when they tracked dead and live trees, log regrowth, front cover, and mule deer feces.

Rogers explained that mule deer graze and browse in Aspen Grove from August through October, when the plants dry out, to stock up on protein for the fall.

In addition, the cows were allowed to graze two weeks a year.

Rogers pointed out that the wildlife and grazing cows mow down the Aspen shoots before they grow into trees.

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