Boulder, Loveland wildfires caused by humans, but scientists debate role pine beetles play

Wildfire season in Colorado took a while to get going but now appears to be in full swing in late summer, with a blaze near Loveland claiming two homes and spreading to 900 acres over the weekend just as firefighters gained the upper hand on Boulder's Fourmile Canyon Fire.

The Denver Post Monday reported Loveland's Reservoir Road Fire, which was 20 percent contained, was started by a homeowner burning slash. The homeowner, whose property did not burn down in the blaze, could face criminal charges.

Meanwhile, Real Vail's sister site, Real Aspen, reported on Monday that “a volunteer firefighter's home fire pit likely triggered the Fourmile Canyon blaze that sent thousands of residents fleeing as 166 homes burned to the ground” in the foothills west of Boulder last week.

Firefighters battling Boulder's Fourmile Canyon blaze.
Boulder Office of Emergency Management

According to the Boulder County Sheriff's Office, the man, whom 7 News in Denver reported was a 71-year-old, 20-year volunteer firefighting veteran, made a fire in his pit a few days before the Labor Day conflagration erupted. He had reportedly doused the pit with water and stirred the ashes, but the sheriff's office reported that strong winds that day caused it to flare back up, spreading embers to the surrounding vegetation.

“The investigation is continuing and it is unknown if criminal charges will be pursued,” the Boulder County Sheriff's Office said in a press release Monday. “For criminal charges to be pursued, the resident would have had to act in a reckless or criminally negligent manner.”

The Fourmile Canyon Fire, which today was declared fully contained, was originally believed to be the result of a vehicle colliding with a propane tank, but that theory likely resulted from misinterpreted radio traffic during the frantic initial reporting of the fire.

Gov. Bill Ritter, who last week issued an emergency declaration and committed $5.2 million to fight the Boulder fire, again on Monday declared the Loveland fire in Larimer County a disaster emergency and set aside $3 million.

Sen. Mark Udall, D-Colo., toured the Boulder fire zone Monday and said he would continue to push for federal funds to clear dead and dying forests in Colorado. He also promised a federal investigation into how similar fires can be prevented in the future.

The Vail Fire Department Monday received U.S. Forest Service approval to continue its beetle kill mitigation efforts meant to create defensible space for firefighters in a perimeter around the town. Crews will cut down 119 dead lodgepole pines south of Bighorn Road in East Vail, about two miles from the East Vail-Interstate 70 interchange.

The project will mark the 12th area to receive treatment in the wake of the ongoing mountain pine bark beetle epidemic. In all, Vail has removed about 1,000 trees on 60 acres this summer, including many dead trees in and around power lines, and crews have been working on thinning forest land around town for four consecutive summers.

Vail Fire Chief Mark Miller says beetle-killed stand of pine trees burn more intensely and are unpredictable for firefighters – sending off more “spot fires” from the main fire resulting from flying embers — but there is an ongoing debate about whether beetle kill makes forests more or less susceptible to wildfire.

University of Wisconsin forest ecologists Monica Turner and Phil Townsend, in collaboration with Yellowstone National Park Vegetation Management Specialist Roy Renkin, are studying the connection between the beetle kill epidemic and wildfire near Yellowstone National Park in Wyoming.

Using NASA satellite imagery of beetle-kill areas and comparing it to areas ravaged by wildfires, they've concluded forests hit hard by the bugs might actually be less prone to wildfires, raising the question of how much money and manpower should be dedicated to mitigation efforts.

Once lodgepole pines lose their needles, there's actually less material for fire to consume, the researchers found. Still, the University of Wisconsin study also concluded that climate change may be helping the beetle epidemic along, while also contributing to more wildfires because of hot, dry conditions in the West.

“While pine beetle attacks may not, in fact, increase fire risk in western forests, Townsend believes fire and beetles do share a connection — climate change,” according to a NASA article on the study.

“Cold winter nights have traditionally kept beetle numbers in check by killing off larvae as they overwinter in trees. In the last decade, winter nighttime temperatures have not dipped as low — an observation predicted by climate change models. More beetles are surviving to damage larger areas of forest. Fires, of course, are also affected by warmer temperatures. As temperatures warm and some areas become drier, many climate scientists predict fires to increase in number and size.”