There lives a giant among us and it has been growing quietly in the deep forests of Utah. Amidst the Fishlake National Forest lies the second largest living organism on Earth. Covered with light-colored bark and yellow leaves, the Pando, or the Trembling Giant, covers an enormous area of the forest.

The Pando, or the Trembling Giant, is a massive grove of aspens situated in the Fishlake National Forest, Utah. The grove consists of about 47,000 trees which are genetically identical and share a single root system. This makes the entire grove a single living organism and one of the largest on the planet.

With their bright colored leaves and dramatic markings on the greyish to white barks, aspens are one of the most beautiful trees. They also possess a unique characteristic. Each of the separate trees that are part of an aspen grove is, in reality, part of one enormous tree. They share the same root system and the roots cover acres and acres of land area. The trees that we see above ground are the shoots that emerge from the roots underneath under favorable environmental conditions.

The aspen trees that are part of the Trembling Giant are a variety called “quaking aspen.” They are so called because they rustle at the slightest breeze producing a fluttering sound. Burton V. Barnes of the University of Michigan discovered the forest in the 1970s. Paul Rogers, an ecologist at Utah State University, has determined the sex of the Pando as male.

The Pando has more than 47,000 trees in its grove. Each of these trees has the same genetic composition. In other words, they are clones of one another making the grove one single living organism. The Organization for Economic Cooperation and Development declared the grove as the “world’s most massive organism” in 1992. Currently, it occupies second place, after the humongous honey fungus that covers 9.6 square kilometers in Oregon.

The Pando encompasses 43 hectares in area and weighs nearly 6,000 metric tons. There are over 40,000 stems, which die independently and are replaced by new stems growing from its roots.

The aspens reproduce via a process called “suckering.” This is a form of asexual reproduction in which an individual stem has the ability to send out lateral roots. These roots, under the right environmental conditions, shoot up erect stems. From above the ground, these stems appear as separate individual trees. But underground, they are all connected to the same root system. The process keeps on repeating and the aspens go on to cover large and areas.

The Trembling Giant is spread across 43 hectares (0.43 square kilometers or 106 acres). The entire grove weighs nearly 6,000 metric tons. Even though the entire grove is a single organism, the death and re-growth of the different parts of the trees are independent.

Experts have estimated the age of the Pando to be around 80,000 years making the Pando one of the oldest beings now alive. This age designation is based on a complex set of factors.

There have been numerous debates when it comes to deciding upon the age of the grove. Normally it’s the tree rings that are used to determine the age of a tree. But that cannot be done with the aspen grove as the trees that are on the ground are part of one massive tree. So, the age had to be determined by examining the roots.

Many complex factors were taken into account to identify the age of the Pando. One such factor is the history of the local environment, soil conditions around the area, the rate of growth of aspen trees, and the distance from sea level. Considering all the factors, the age of the Pando was calculated to be around 80,000 years. This means that the Pando was there before the human civilization that we know today started. This makes the Pando the oldest living organism on the planet!

Unfortunately, the future of the giant appears gloomy. The trees are constantly deteriorating from drought, beetles, diseases caused by fungi, and overgrazing by cattle.

It is common for the stems of the Pando to be prone to attacks by pests, diseases, and natural calamities. They die and then are again regenerated by the roots. But new evidence suggests that the roots are under attack. This had led to a decline in the regenerative capabilities of the roots. Dead stems are not being regenerated. If this continues, the grove will start diminishing in size.

As of 2013, a restoration project is underway to preserve the Pando. Parts of the grove have been fenced off allowing new stems to grow without any external disturbance such as cattle grazing. Studies are being carried out on the trees to learn more about them and identify ways to save them.
[source: 1,2,3]