One of the oldest and largest organizations in the world is dying, and it's mainly our fault

One of the most important organisms in the world, a genetically identical tree forest located in Utah, is slowly being devoured by deer.

The Pando Aspen colony, also known as the "trembling giant", has probably survived for thousands of years. But about 80% of this population is in a perilous state, according to a new article published today (October 17th) in the journal PLOS One.

The trembling giant, weighing 13 million pounds. (5.9 million kilograms) and covering 106 acres (0.42 km 2) of the Fishlake National Forest of Utah, includes more than 47,000 genetically identical stems from a single underground parent clone. [Quaking Aspen: Trees of the Mountain West]

In this new study, a group of researchers measured the health of different parts of the forest, including counting live trees versus dead trees, counting the number of new stems, and tracking the droppings. Animals fallen for a bite. They found that the biggest obstacle to the best indicator of forest health – if new shoots could survive – was the mule deer.

It's natural for older stems to disappear, Paul Rogers, director of the Western Aspen Alliance and associate professor at Utah State University, told Live Science. What is unnatural is that the new stems do not grow, he said. Over the past two decades, mule deer and cattle have devoured all new stems from the underground mother, Aspen Aspen. In most areas, there is no "young or middle-aged trees at all," he said. So the forest, to use human terms, is made up "entirely of very old people," said Rogers.

Aerial photographs of decline

Rogers and his team also compared aerial photographs of the area spanning 72 years and revealed that the aspen forest had thinned. In 1939, the treetops were all affected, but from the 1970s, "we see a lot of spaces between trees," he said. This means that old trees are dying and new ones are not coming to fill the gaps.

Part of the problem is that game such as mule deer do not have natural predators in the area. In the early 1900s, humans killed most natural predators, such as wolves and grizzlies, Rogers said. Most of Pando's lands are now reserved for recreational activities, such as camping, where mariners are protected from hunting. "Deer know it very early and find that it's a safe harbor."

But in reality, "Pando fails because of human decisions," Rogers said. "Humans control wild animals, especially game species such as deer and elk."

Part of the trembling giant is in full swing. This area was closed around 2013 and in five years, thousands of stems – ranging in height from 3.6 to 4.5 m (12 to 15 feet) – have increased per acre, Rogers said. Here, the fence seems to work. Half of the area occupied by the aspen clone is unfenced and easily accessible by mule deer and livestock. About 30 percent of the area is fenced with a fence 2.4 meters (8 feet) high, Rogers said. But "the fence is not doing its job, so it's also in bad shape," he said. "In one way or another, the animals keep coming in – it's kind of a mystery to us," he said. He thinks the mule deer (not the cattle) is jumping on it.

"We need to help control animals – deer and cattle – and give Pando a break so he can recover," Rogers said. This can be done by reducing their numbers, limiting them with fences that work properly, or preventing them from leaving the area, as traditional predators have done, he said.

"We are not just talking about the tree, but about all the plants and animals that depend on it," Rogers said. "We can not manage wildlife and forest independently, we need to manage them together and in coordination with each other."

And the approaches that work to protect Pando could be extended to Aspen around the world, he said.

Originally posted on Live Science.