GRAND LAKE —With the Big Meadows fire, stands of graying trees left by the bark beetle were only a small part of the equation.
Contrary to widespread belief, the dead trees lingering after the beetle epidemic don’t necessarily cause greater wildfire risk. Numerous studies conducted and analyzed by the University of Colorado Boulder, Colorado State University, the Colorado Forest Restoration Institute and the University of Idaho have found no relationship between insect outbreaks in forests and subsequent fire activity. Instead, fire risk seems to revolve around drought.
“It wasn’t the beetles that caused the (Big Meadows) fire, they’re just one small piece of the landscape,” said Kyle Patterson, public information officer at Rocky Mountain National Park. “The beetles going through there had an impact of how the fire burned, but one of the bottom lines is when you have a drought, when it’s hot, dry, and windy, you can have large fires.”
According to National Park Service information, the Big Meadows fire won’t officially be called “out” until the winter snow, but it is 100 percent contained. It burned 653 acres and cost $2.5 million.
According to Mike Lewelling, fire management specialist at the Park, a number of elements came together to fuel the fire. The fire ignited after a lightning strike at the bottom of a steep slope, which allowed the fire to get into crowns and move uphill quickly. The fire started in early June, when living spruce trees hadn’t yet greened, making them susceptible to burning. Tall grasses in nearby meadows were still cured, allowing the fire to move over standing springtime water.
These conditions, in addition to dead stands of beetle-killed pines, resulted in what Lewelling called a fuel “jackpot.”
Over the course of a day, on June 11, the fire grew from two acres to around 400 acres.
But Lewelling also cautions against assuming dead lodgepole stands contributed significantly to the fire’s spread.
“The Cow Creek fire in 2010, on the east side (of the Park), had very little beetle kill, and it was at about the same time (of year),” he said. “But it ran through crowns like nothing.”
The Cow Creek fire consumed around 1,500 acres before being contained – more than twice the extent of Big Meadows.
“So, when it’s hot, dry and windy, you get things to burn,” Lewelling said. “Beetles are just one part of the whole equation.”
Beetle kill does, however, play a major roll in how fires are fought.
Prior to the outbreak when the forest was green, Lewelling said fire crews could have moved up slopes, cut trees and put out the fire more easily. But downed and weakened trees create significant hazards for firefighters.
“We’ve had close calls with employees in the Park and others,” Lewelling said. “They have a tree fall, and didn’t hear it coming down until it hit the ground.”
Lodgepoles’ shallow roots create falling hazards, especially after they’ve been dead for several years and begin to rot. When weighing these risks, Lewelling had crews approach the fire with caution. He pulled them in at night when visibility was especially bad, which allowed the fire to recharge. Dead fuels, including beetle kill, allowed materials to burn longer and keep heat overnight.
“When you talk about beetle kill and fire, that is the most significant story,’ Lewelling said. “It’s always in the back of our minds. The way we approach fires has changed drastically.”