Treasure Valley residents headed for the hills this summer will find a now-familiar scene: charred tree trunks instead of thick-needled pines in many of their favorite places.
It's the lingering result of recent wildfires such as the 190,000-acre Pioneer Fire, which burned through the Boise National Forest, or the 95,000-acre Tepee Springs Fire north of McCall. A thick carpet of pink fireweed will soften the blow, and portend the new beauty to come as the forests heal.
This is summer in the 21st century in the American West, but not all of our forests are healing. And with our warmer winters and summers, many parts of the West should expect to see significantly more fire activity in the next two decades. Up to five times as much land may burn as was consumed by fires in the previous 20 years.
Add both together and our backcountry is going to be very different in the years to come.
“We need to start expecting that these landscapes aren't going to look the same in the future, whether it's reduced density of trees or no longer a forest,” said Camille Stevens-Rumann, assistant forestry professor at Colorado State University.
Two new reports help illustrate that future. One team of researchers, including Stevens-Rumann, examined how forest sites in five states recovered from wildfires. A second group used climate data to forecast future burn areas across the West.
To understand their conclusions, it helps to review where we've been.
30 years of fire
The West has seen repeated destructive megafires over the past 30 years, ever since lightning hit a tree in Yellowstone National Park's Lamar Valley and started a fire on May 24, 1988.
The park's first fire of the 1988 season ended a few hours later as it had begun - naturally - when rain from the thunderstorm that spawned it snuffed it out. But other fires soon followed. More than 700,000 acres burned in and around the park that year, a signal to the nation that something was changing.
Earth was getting warmer as greenhouse gases rose due to more than a century of fossil fuel burning, beginning with the Industrial Revolution.
The fire seasons grew longer. The warmer Julys and Augusts allowed what would have been relatively benign fires to become megafires in Lowman, Oakland, Los Alamos. New Mexico, and, in 2017, Santa Rosa, California.
Westerners have become accustomed to spending weeks under a shroud of smoke. We take for granted that the landscapes we love will at some point go through a sudden transformation, from lush green forests of tall pines and firs to blackened hillsides with standing ashes of dead trees. Roads are closed, river trips are delayed, campers chased away. Far worse, some communities have seen neighborhoods destroyed and residents killed.
These are the past 30 years of fire in the West, a period unequaled since settlement began in the 1840s. This new reality culminated in 2017 in a record fire season that burned 10 million acres, killed dozens of people, and destroyed more than 6,000 homes and other buildings.
Federal wildland fire experts predict another long season this year.
The heavy rains last week added to the above-average snowpack in much of the state, which will delay the season's start in the mountains, even as it beefs up the grasses and other fine fuels across Idaho’s rangeland.
Dry conditions and hot temperatures are forecast for much of the West this summer, including Southern Idaho, said Jeremy Sullens, a wildfire analyst at the National Interagency Fire Center in Boise. Fire season now continues deep into October, 70 days longer than in the 1980s.
'It's going to be a lot worse'
Forest and fire scientists say the past is only the beginning.
North Idaho is among parts of the West that can expect to see more than five times the area burned during the next 20 years than fires covered in the past 20.
That trend is expected to continue across the Western U.S. and northwestern Canada, though not uniformly, according to the recent study by forest scientists Thomas Kitzberger of Argentina, Don Falk and Thomas Swetnam of the University of Arizona, and Leroy Westerling of the University of California, Merced.
The scientists predict the regions with the most burned land will also include western Montana, western Wyoming, central Utah, northern Colorado, northern Arizona, western Nevada and the whole of New Mexico. In many areas the actual burning on the ground has exceeded the models, said Westerling.
"It's going to be a lot worse," he said.
More fire is not necessarily bad. What matters is how much burns "severely," which means under the hottest, driest conditions driven by high winds.
Indeed, U.S. Forest Service Acting Chief Vicki Christiansen said we need to treat 40 percent of the landscape if we are going to make our forests more resilient and able to adapt. The cheapest way to do much of that treatment would be through intentional burning in the wetter, cooler seasons.
Living with fire
We can steer these fires away from our communities, and through management we can make them less severe. But we will have to learn to live with a level of fire we never envisioned in the decades before Yellowstone’s fires captured the nation’s attention.
“Clearly we don’t have a choice,” said Penny Morgan, a fire ecologist at the University of Idaho, whose career has spanned this era of megafires. “Having no fire or no smoke is not one of our options.”
Morgan and Stevens-Rumann were a part of a team of researchers who analyzed data from nearly 1,500 sites in five states — Colorado, Wyoming, Washington, Idaho and Montana — measuring more than 63,000 seedlings across 52 wildfires that burned over the past three decades. They sought to understand how changing climate affected post-fire tree regeneration, a key indicator of forest resilience.
One of the areas they studied was the Lowman area on the Boise National Forest. There, the team found sites with no sign of regeneration.
“We are going to lose some forests,” Stevens-Rumann said. "In those lowest elevation forest sites like that area around Lowman, we are likely going to lose them.”
But the news is not all bad. On sites that aren’t as dry, they found lots of seedlings, showing the forest would naturally regenerate itself.
“If you think of some of those high-elevation forests, like the area around Warm Lake, we found an abundance of seedlings,” Stevens-Rumann said.
Even planting trees won’t work if the climate has changed so much that the trees that grew on a site can’t grow back. But the Forest Service is studying different species to see which ones can survive moving forward in a drier, warmer world, Morgan said. They also are using strategies like planting in the middle of a burn; if an area reburns in a relatively short time, within 25 years, the new trees will be protected by the open area.
Overall, Stevens-Rumann said, we have to learn to be comfortable with fires burning when the conditions are not so severe. That means beginning prescribed burning soon after the snow melts, until it gets hot and dry, and then starting again late in the fall.
“It's taking the small risk now to avoid the big risk later,” she said.
Southern Idaho is not expected to have as much fire as North Idaho in part because up to 75 percent of its national forests have burned in the past 30 years. But it still has gaps of large, unburned forest, such as the Sawtooth Wilderness front south of Stanley.
Stanley Mayor Steve Botti worries that a fire in the height of the tourism season would seriously hurt local businesses, along with threatening homes and lives. The Salmon-Challis National Forest is beginning a program to treat the forest with thinning, logging and prescribed burning, beginning in the Cape Horn area west of the Sawtooth peaks.
Botti and others sought the treatment for more than five years. Now, he just hopes it gets done in time.
“I cross my fingers every year, hoping we can escape one more year,” Botti said.