The oldest and largest organism on Earth can't escape from moose and deer: it's being eaten alive.

In the Wasatch Mountains in the western United States, hidden in the slopes above a lake for over 14,000 years, lies the largest organism on Earth. Weighing approximately 6,000 metric tons, it holds the title of the largest organism in the world. Recently, scientists have made a concerning discovery — the organism is literally being eaten alive, reports Science Alert.

This organism is known as Pando, which appears to be an ordinary forest filled with individual trees that have bright white bark and small leaves swaying in the wind. However, it is actually comprised of 47,000 genetically identical stems growing from an interconnected root system. Researchers believe that Pando has existed for about 14,000 years and covers an area of around 43 hectares.

Poplar trees form clonal groves in various locations, but Pando is unique due to its immense size. Most similar clonal poplar groves in North America are significantly smaller, with an average area of about 1.2 hectares in the western United States.

Previous studies have indicated that Pando is around 14,000 years old, although most of its stems only live for about 130 years. Nevertheless, the longevity of this organism and its remoteness contribute to an ecosystem that includes 68 plant species, with many animals having evolved and thrived in the shade of Pando.

As a result, the entire vast system depends on the health of the aspen. Today, Pando is protected by the U.S. National Forest Service and is not threatened by logging; however, scientists are alarmed that Pando is vulnerable due to a number of other factors.

The Largest Organism on Earth is Being Eaten Alive

One of the primary threats to Pando is overgrazing by deer and moose. Once, wolves and cougars kept these populations in check, but their numbers have significantly increased as predators have vanished.

Pando also attracts deer and moose, as the protection provided by the forest shelters them from hunting. When old trees die or fall, sunlight reaches the forest floor, stimulating the growth of new clonal stems. However, when these moose and deer consume the tips of the newly forming stems, they die. This results in minimal new growth across large areas of Pando.

In simple terms, the largest organism on Earth is indeed being eaten alive. Fortunately, there is one area that has been fenced off for several decades to save the dying trees. Researchers have excluded deer and moose from this area, leading to successful regeneration of new clonal stems, resulting in a dense growth known as the "bamboo garden."

Another Threat to Pando

According to Richard Elton Walton, a biology research fellow at Newcastle University, the old stems of Pando are also suffering from at least three diseases:

• canker disease;
• leaf spot;
• fungal disease known as conk.

Although plant diseases have developed and thrived in poplar groves for millennia, the long-term consequences for the ecosystem are unknown, especially given the lack of new growth and the ever-growing list of other pressures on the clonal giant.

Another concern for scientists is climate change. Pando emerged after the last Ice Age and has since dealt with a primarily stable climate. Of course, it resides in an alpine region surrounded by desert, meaning it is not unfamiliar with high temperatures or droughts. However, climate change threatens the size and longevity of the tree, as well as the entire ecosystem it supports.

Hope for Pando

Nevertheless, Pando is incredibly resilient and has previously survived rapid environmental changes, especially when European settlers began to inhabit the area in the 19th century. Then, in the 20th century, there was a rise in recreational activities. Throughout its history, Pando has also faced diseases, wildfires, grazing by livestock, and officially remains the largest scientifically documented organism in the world.