By Katie Valentine , 9/6/2014

Pine beetles are devouring forests around Mount Rushmore, causing property values to fall and leading to worries that the tourism industry will suffer too.

As Bloomberg reports, pine beetles have destroyed 25 percent of South Dakota’s Black Hills forests, the region that houses the famous carving of George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Roosevelt’s heads. Mount Rushmore is a key element of the region’s $2 billion-a-year tourism industry, and the beetles, coupled with (and likely fueled by) drought, have destroyed 38,000 square miles of overstocked forests — an area the size of Indiana and Rhode Island combined.

Officials are worried that, as more and more dead trees blight the horizon, tourists will be turned off from visiting the region’s forests.

“There is always the question, ‘When is the Forest Service going to take all the dead trees away?’” Catherine Ross, executive director of the Winter Park-Fraser Chamber in Colorado, said. “I talk to them about the enormity of the problem. There are just so many dead trees out there.”

In Colorado, some towns have taken the problem into their own hands. In the tiny town of Grand Lake, voters approved a $4.2 million bond to remove as many as 400,000 trees from a large golf course. And Winter Park recently passed a property tax for beetle treatments, in the hope of slowing the beetles’ spread into the community. The town is also helping Winter Park Resort keep track of how many acres the beetles have destroyed so far.

Colorado Gov. John Hickenlooper sent a letter to Agriculture Secretary Tom Vilsack earlier this year, in which he told the secretary of the “unprecedented damage” wrought by pine beetles and spruce beetles in Colorado’s forests.

“This damage is likely to continue given the significant drought conditions that we are experiencing in Colorado, that further reduce the health and resiliency of our forested lands,” the letter reads.

Pine beetles are native to the forests of the Western U.S., but climate change has caused their populations to explode in recent years. Cold winters that used to kill off many of the beetles aren’t occurring regularly anymore, which means the beetles have a much longer breeding season than they had in the past. Warming temperatures, too, are allowing the beetles to spread into higher latitudes than they were previously able to. The current pine beetle outbreak might be the largest insect outbreak ever seen in the U.S. — as of May 2013, mountain pine beetles have killed major swaths of ponderosa, whitebark, lodgepole, Scotch, and limber pines in all 19 western U.S. states and in Canada’s Western provinces. The beetle infestation, along with disease, threatens 94 national forest areas in 35 states.

Other climatic changes, such as drought, can cause an explosion in beetle numbers. Trees under stress from lack of water have less strength to put up defenses against the beetles, which makes it easier for the beetles to kill the trees and continue to breed. The beetles are also helping contribute to climate change — by killing trees that store significant amounts of carbon dioxide, pine beetles are creating a positive feedback loop that accelerates climate change.

Source: thinkprogress.org