What is normal for fires these days has changed, says Ed Delgado, the chief forecaster for the National Interagency Fire Center in Boise. Smoke-shrouded cities, community evacuations and backcountry closures have become the norm in Idaho over the past 20 years as the size and ferocity of wildfires has grown.
Since 1992, Idaho has had 568,000 acres burn annually, making it the wildfire capital of the continental United States. Only Alaska has had more acres burn.
About 1,400 of the 4,900 largest fires from 1992 to 2012 were caused by careless people, the data shows. About 1,200 more than that were caused by lightning.
And some of those were deadly, with 22 firefighters dying in Idaho from fires, traffic accidents, and plane and helicopter crashes since 1992.
When the snowpack disappeared across much of the state by the end of March, fire officials were concerned that the wildfire season could be a bad one. But steady rainfall this spring has kept the forests moist and the rangeland green.
“I heard the news that all of Idaho was in some kind of a drought when it was pouring down rain at my house,” said Delgado, NIFC’s manager of predictive services. “It’s going to take some pretty hot weather to dry things out anytime soon.”
Weather and climate conditions will have different effects on the sagebrush-covered rangeland in the south, the Ponderosa pine forests of Southwest Idaho, the high-elevation lodgepole pine of Central and Southeast Idaho, and the hemlock and cedar forests of Idaho’s Panhandle.
In the southern part of the state, the Department of Interior has put in place a fire plan to protect the sagebrush ecosystem critical to the survival of sage grouse. It is under review for protection under the federal Endangered Species Act. Huge fires over the past decade have transformed much of its habitat from native shrubs and bunch grasses to a sea of alien cheatgrass, which dries out earlier and increases the frequency of wildfires.
The wet spring has helped the grass grow thick and tall, said Mike Guerry, a rancher in Three Creek southwest of Twin Falls. As the head of his local rangeland protection association, he’s watching how the heavy grass dries, but he was certainly glad to see the rain.
“We really needed it,” he said.
The National Oceanic and Atmospheric Administration is predicting El Niño conditions, which are unusually warm surface temperatures in the equatorial Pacific Ocean. Historically that means fewer fires because it brings rain-producing thunderstorms on a regular basis, Delgado said.
The lightning these storms bring would add to the fire danger under dry conditions. Still, it’s Idaho, so that’s possible.
“Fire is a natural part of our summers,” Delgado said. “We’re still going to see fires.”
Fires have been frequent in Southern and Central Idaho recently, but the Panhandle has seen a long stretch of little fire. From 1985 to 2012, only 31,000 acres burned from the St. Joe River watershed north to the Canadian border.
But this year the snowpack was gone by April 1, and it’s one of the few places identified on NIFC’s fire potential map as having an increasing to above-normal potential in June. All of North Idaho and the western slopes of the Payette National Forest are rated above normal for fire potential in July and August. As are all of Oregon and Washington.
Jonathan Oppenheimer, the Idaho Conservation League’s forest expert, said it takes extreme conditions to get the kind of big fires that have burned regularly in Southwest Idaho to burn in the Panhandle.
“People describe it as the asbestos forest,” Oppenheimer said.
A 1910 fire there burned millions of acres in the region, when a series of windstorms combined with hot temperatures in a perfect storm. Much of the area hasn’t burned since.
Idaho State Forester David Groeschel said his staffers are seeing dry soil and understory conditions that could become dangerous later.
“Already we’re seeing a fair amount of fire activity we wouldn’t normally see until July and August,” Groeschel said.
North Idaho has had rain the past two weeks, he said, which has helped.
“If the moisture shuts off and we get some hot, dry weather and we get a dry lightning front come in with a lot of wind, there’s a lot of fuel out there,” Groeschel said.
About half of Southern Idaho’s forests have burned over the past 30 years, which Interior Department fire official Dick Bahr said in 2012 had brought the area into its historic range for fire after decades of suppression had increased the fuel load and made it more vulnerable. There remain huge swaths of forest that have not burned, most notably the core of the Sawtooth National Recreation Area.
The impacts of fires are determined by location. A 100,000-acre range fire in predominantly cheatgrass has relatively few negative impacts compared with a several-thousand-acre fire in the foothills of a city such as Boise or Pocatello.
That’s why firefighters urge homeowners to clear flammable material away from structures and create defensible space. Oppenheimer says even more must be done.
“We really need to focus on limiting the expansion of homes into the dangerous areas,” he said.