Beetles And Global Warming

How a tiny bug is ravaging Colorado's forests
By Jim Moscou | Newsweek Web Exclusive
Jul 22, 2008

Summer at Colorado's Beaver Creek Resort is usually a time of hot days, cool nights, verdant views and the peaceful sound of the Rocky Mountains. Not this year. The area's idyllic silence is being disturbed by the sound of chainsaws cutting down large swaths of dead or dying trees in this gated community. "We have no illusions, no choice," says Tony O'Rourke, executive director of Beaver Creek's Home Owners Association. "We can't stem the tide." O'Rourke's dire tone comes from the resort's lost battle with a bug--the mountain pine beetle--that is destroying much of Beaver Creek's lush green vistas and reducing them to barren brown patches.

After ravaging 22 million acres of pine trees in Canada over the last 12 years, the rice-sized insects have been feasting their way southward. Their favorite meal: the majestic lodgepole pine, which makes up 8 percent of Colorado's 22 million acres of forests. Before landing in Beaver Creek, the pine beetles tore through neighboring Vail, Winter Park, Breckenridge and several areas around Steamboat Springs. So far, say state foresters, the beetles have eaten through 1.5 million acres, about 70 percent of the all the state's lodgepole pines. The tree's entire population will be wiped out in the next few years, Colorado state foresters predict, leaving behind a deforested area about the size of Rhode Island.

The last significant Colorado outbreak was recorded in the late 1970s and was, by most accounts, far less devastating than the current infestation. "This the most extreme [beetle outbreak] in recorded U.S. history," notes Tom DeLuca, a senior forest ecologist for The Wilderness Society, which has tracked the epidemic.

Coming up with solutions isn't easy. "It's clear these beetles don't read the book," says Ingrid Aguayo, the top forest entomologist for the Colorado State Forest Service and a lecturer at Colorado State University. The beetles are breaking all the rules taught in forestry school. The last few relatively warm winters have allowed the beetle population to flourish and enabled them to attack trees at much higher altitudes, like the 10,000-foot forests around Beaver Creek. Also, the current beetles are also proving to be less picky eaters than their predecessors. Today's bugs are even attacking small trees, further endangering any chance for new growth. There is some evidence, too, that the beetles are hatching and taking to flight earlier in the year, giving them longer summer days to do damage.

Is there an unequivocal reason for beetles' advance? "They have food," Aguayo adds, noting that drought conditions in Colorado in the early 2000s weakened trees, and after decades of fires suppression, many lodgepole pine stands are more than 80 years old, moving toward the end of their lifecycle and thus vulnerable. "The stars are aligned," Aguayo says. "It's a perfect storm for [the bugs] to do well." Untended, the situation could prove deadly very soon. With summer in full swing, wildfire in the high country is on everyone's mind. Lodgepole pines can stand 80 feet tall. But once beetles leave them for dead, the trees transform into giant matchsticks. The fire danger they pose has even forced some Colorado campgrounds to close until further notice.

Another concern: That the bugs' eating habits may change. For decades, foresters have lived by a theory that when beetles kickoff their feeding frenzy, they chose a particular tree species as their target. For instance, in the 1970s Colorado outbreak, the favored flavor was ponderosa pine, a cousin of the lodgepole. This time around, foresters are worried the beetle will make a species jump. The result could not only be another decade of watching dying forests, but infestations at lower altitudes and in areas more populated, like the foothills just west of Denver, Colorado Springs and Boulder. "We'll know in the next year or two," says Aguayo. "It's a very tense time."

The Tree Study
The Climate Change Study