Beetles serve up wildfire kindling

Beetles serve up wildfire kindling

8 October 2006

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Casper, WY, USA — The scorched sticks jutting from a floor of fine, gray ash in what was once a thick forest tell the story: The Tripod fire that roared through north-central Washington this summer burned hot, fast, and in some places, furious.

The dead and dying trees that escaped the fire spin yet another tale. Across the West, beetles have damaged or killed entire swaths of trees weakened by drought, creating fuel for spectacular wildfires. The Tripod blaze was a prime example, scorching more than 273 square miles of the Okanogan and Wenatchee National Forests.

Insects don’t determine whether a fire starts or its severity — drought and weather play an even bigger role — but they can exacerbate wildfire conditions in a tinder-dry forest.

“The fuel situation, I don’t think anybody would tell you, is going to improve any time soon,” said Mike Fitzpatrick, a National Park Service retiree who has also worked for the Forest Service and Bureau of Land Management. “It’s going to be the careers of people coming into fire management for the next 30, 40 years.”

Forest Service officials are still working to map how their forests have been altered by bug kills in 2006. In 2005, mapping showed some 8.6 million acres of forest in 12 Western states, including Alaska, were infested with beetles, according to information provided to The Associated Press.

They also don’t track the impact beetles have on fire activity, but in some places, their role can’t be ignored.

The Pinnacles fire in southern California burned 2,730 acres, some of it vegetation killed by insects, said Bob Sommer, vegetation specialist for the San Bernardino National Forest.

A handful of fires burned in standing dead or downed timber in Idaho’s Rocky Mountains, including the Potato fire, which burned more than 18,000 acres of the Salmon-Challis National Forest. Still smoldering is Washington’s Tripod complex, two lightning-sparked fires that burned together in dense timber, much of it killed by insects.

Foresters first began noticing beetle attacks on lodgepole pines in the Okanogan and Wenatchee National Forests in the 1970s. The trees there likely were established more than 100 years ago and are now reaching maturity, said John Townsley, a forest silviculturist.

They also have grown to thick stands, competing for less water, making them more susceptible to beetles. Like fruit flies are attracted to bruised fruit, beetles tend to go after trees that are already stressed.

The infestations alter the landscape in patches. Bugs may kill just five or 10 trees one year, but if the infestation continues in the same area, the dead fuel accumulates over time.

Researchers at the Fire Sciences Laboratory in Missoula, Mont., are working to map all the fuels and vegetation for the United States, beginning in the West. Using that information, computer models will allow fire managers to predict the growth and severity of wildfires and plan their attack, said Kevin Ryan, land fire program manager at the laboratory.

So far, though, a lack of research prevents fire managers from attributing extreme fire activity to beetle kills, Ryan said.

“The dynamics of the fuel depend on forest type, heat, moisture. You can’t make a universal statement about whether or not there’s more or less hazard just because the beetles have occurred,” he said.

“I’ve joked for years, ‘If the fire doesn’t kill, then the bark beetles will. If the bark beetles don’t kill, then the fire will,”‘ he said. “One of the certainties of life is that you can’t get out of it alive, and the same is true for forests. It’s the dynamic of the forest.”

In Colorado, where bug kills have spread from patches of forest to entire hillsides, the beetle problem has been recognized by more than just foresters: Real estate agents in at least one county are voluntarily warning that a pine-beetle infestation could erode home values.

No large fires were experienced in the dead timber there this year, “But boy, I tell you what, it’s prime and ready to go,” said Steve Torbit, senior scientist for the National Wildlife Federation there.

Torbit also raised concerns that beetles could spread to species that are not yet experiencing beetle problems, such as the ancient bristlecone or limber pines that are less plentiful but provide important habitat for wildlife.

In the meantime, foresters across the West are working to alleviate hazards posed by beetles.

Colorado officials are thinning trees, creating fire breaks near communities and even spraying individual trees in some high-risk areas, said Janelle Smith, spokeswoman for the Forest Service regional office.

Foresters also are working harder to reintroduce fire into hard-hit areas — a tremendous undertaking when millions of acres are at stake, Fitzpatrick said.

Insects appear to be moving into higher elevations that are seeing warmer temperatures. That could be contributing to a recent rise in wildfires at higher elevations, as well as to safety concerns fighting fires in those areas, he said.

“If we don’t go out and do this on our own, we’re going to have to go out and do it at nature’s pleasure,” Fitzpatrick said. “And nature tends to start them at the worst time, in the worstplace.”


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