One of the largest organisms in the world, a Utah forest of genetically identical trees, is slowly being devoured by deer.
The Pando quaking aspen colony, also known as the "Trembling Giant," has likely survived for thousands of years. But about 80 percent of it is in a perilous state, according to a new paper published today (Oct. 17) in the journal PLOS One.
The trembling giant, weighing 13 million lbs. (5.9 million kilograms) and covering 106 acres (0.42 square kilometers) of Utah's Fishlake National Forest, comprising over 47,000 genetically identical stems that grow 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 various parts of the forest, as by counting the number of living versus dead trees, counting the number of new stems and tracking the feces of animals that dropped in for a bite. Paul Rogers, the director of the Western Aspen Alliance, said they were "the greatest obstacle to the strongest indicator of the forest's health."
It's natural that the older stems are dying off and adjunct associate professor at Utah State University, told Live Science. What's unnatural is he said. For the past couple of decades, mule deer and cattle have been sprouting from the underground mum asp. In most areas, there's no "young or middle-aged trees at all," he said. Rogers said.
Aerial photographs of the decline
Rogers and his team also compared to aerial photographs of the area that spanned 72 years and found that the aspen forest has been thinning. Back in 1
Part of the problem is that game as well as mule deer do not have natural predators in the area anymore. In the early 1900s, humans killed off most natural predators, such as wolves and grizzly bears, Rogers said. Now, most of the grounds at Pando are set aside for recreational uses like camping, where the browsers are protected from hunting.
But really, "Pando is failing because of human decisions," Rogers said.
There is one part of the trembling giant that is thriving. This area was fenced in around in 2013 and within five years, thousands of stems – some 12 to 15 feet (3.6 to 4.5 m) tall – have been growing by acre, Rogers said. Here, the fence seems to be working. Half of the area that the aspen clone takes up is unfenced and easily accessible by the mule deer and cattle. Around 30 percent of the area is fenced in with an 8-foot-tall (2.4 meter) fence, Rogers said. But "the fence is not doing its job, so it's in a poor state," he said. "Somehow, the animals are still getting in – it's a bit of a mystery to us," he said. He thinks the mule deer (not the cattle) are jumping it.
"We need to help control the animals – both deer and cattle – and give Pando a break so that it can recover," Rogers said.
"We're not talking about just the tree, but we're talking about all the plants and animals dependent on it, "Rogers said.
And the approaches that work to protect Pando could be extended to aspens around the world, he said. 19659002] Originally published on Live Science.