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In July 2021, lightning struck a tree on a rocky ridge deep in a national forest in California near the Nevada border. The US Forest Service decided that it was too risky to tackle at that spot, and that scarce firefighters would be more useful on other blazes—36 burned through California that month. Twelve days later, winds pushed the fire downhill, where it ended up burning 14 homes. The Forest Service sent firefighters, helicopters, and tanker planes to what became known as the Tamarack Fire on the day the winds changed, but local politicians blamed the agency for “allow[ing] this wildfire to burn in lieu of immediate full suppression” and called for more aggressive tactics.

National forests often get the blame for wildfire conditions in the West, says Christopher Dunn, a fire ecologist at Oregon State University. But more importantly, the Tamarack Fire isn’t representative of the fires that threaten most Westerners. According to recent research co-authored by Dunn, and published in the journal Scientific Reports, fires beginning in national forests are “a rare occasion.”

Instead, “those ignitions are more likely to come off private land and move into national forest or into communities,” Dunn explains.

That finding could have profound implications for how the US develops national policies to manage fire—beginning with a 10-year wildfire crisis strategy released by the Forest Service last fall. “It might make sense to do work in the forest to protect the forest, but if our goal is to protect communities, we have to do this work right around home,” says Courtney Schultz, the director of the Public Lands Policy Group at Colorado State University, who was not involved in the research.

People cause wildfires

According to the new research, between 1990 and 2019, about 35,000 buildings burned in wildfires in the 11 western states between New Mexico, California, Washington, and Montana.

There were 91 extremely destructive fires, which each burned more than 50 buildings. But only a quarter of those ultra-destructive fires began in national forests. And those fires only caused 15 percent of the total home damage during the two decades.

“I don’t necessarily think I had the intuition that there was more fire burning onto our land,” says Matthew Thompson, a fire researcher at the Forest Service’s Rocky Mountain Research Station, and coauthor on the paper. “This is a problem that has risk factors and mitigation measures that have nothing to do with managing a forest.”

[Related: Wildfires could hit your hometown. Here’s how to prepare.]

The biggest of those risk factors for massive fires came from humans. Fires were most common when about 150,000 people lived around the burned area, and when there were lots of roads crossing a national forest. Only two of the 91 destructive fires that began in national forests were started by lightning; the rest were caused by people.

“Part of what this research is showing is that risk is not primarily coming from Forest Service land, it’s also coming from the community itself,” says Schultz. Critically, the research found that the most destructive fires burned in hot, windy conditions, meaning it’s unlikely that they could be prevented by thinning out surrounding forests.

It’s true that increased fuel loads have made Western forests more likely to burn in sweltering, dry conditions. But that has more to do with a lack of regular fire, which clears away grass, bushes, and dead wood, than logging. (The trunks of mature trees aren’t the main source of fuel for most blazes.) Climate change is also leading to drier, hotter summers, where fires are more common and intense. 

A report released Wednesday by the United Nations found that by 2050, there will be 30 percent more wildfires across the planet every year. And in the US, more homes are built in suburbs or rural areas near forests or flammable grasslands than any other environment, magnifying the threat. A 2014 paper, coauthored by Thompson, described the “wildfire paradox,” in which fire suppression succeeds 99 percent of the time, but dramatically increases the risk of blazes that are impossible to control. In cases like the 2018 Camp Fire, which killed 85 people, flames explode across the landscape, eating up miles at a time. (The Camp Fire primarily burned private lands, but it’s not clear if it started on or off national forest acres.)

“If we’re just focusing on the federal lands,” says Dunn, “we’re not going to end up in the place we need to be to protect people. We all have a shared responsibility.”

Who handles a crisis?

Last year, the Forest Service, which oversees 300,000 square miles of national forest, announced a “wildfire crisis response” plan that seeks to treat 50 million new acres of Western forests over the next decade, both on and off public land. The latest federal infrastructure bill set aside several billion dollars to meet that goal.

Forests are a key part of the puzzle in fire management: It’s about more than protecting homes, as several experts pointed out to PopSci. In denser woodlands, management can mean reintroducing mild fire, making them less prone to catastrophic burns, or supporting wildflowers and grasses, which in turn provide habitat for butterflies and birds. In Southern California’s oak woodlands and the Rocky Mountain’s ponderosa stands, low-intensity burns can even sequester carbon.

“If we’re just focusing on the federal lands, we’re not going to end up in the place we need to be to protect people. We all have a shared responsibility.”

— Christopher Dunn, fire ecologist at Oregon State University

“When we look at [year-round fires], continuing fuel build up, climate change, and the [growing] wildland-urban interface, we don’t see anything changing until we intervene,” says Brian Ferebee, a senior executive at the Forest Service who is leading the wildfire crisis strategy. The agency has historically thinned or burned two million to three million acres a year across the entire country, which he says, “is not commensurate to address the wildfire issue.”

Ferebee says that the Forest Service is still developing goals for the impact of the plan, rather than just its implementation. “There are a number of values that the public is interested in more than acres treated or timber sold,” he says. “It’s about what level of improvement has occurred to the watershed, or to what degree have you enhanced wildlife habitat, or how have you mitigated impacts to vulnerable communities?”

He notes that those will be shaped both by Forest Service research and by community roundtables, which began this spring. “We know we need to speak to that,” Ferebee says. “I can’t describe to you how we’re going to measure those outcomes, but we know they’re critically important.”

But if the country’s goal is to prevent damage to communities, the research suggests that cities, counties, and states will also need to step up. As the 2014 paper put it, “wildfires are inevitable, but the destruction of homes, ecosystems, and lives is not.” 

Living with fires

The biggest threats to homes, Dunn says, are showers of embers that blow onto a roof or wall, rather than flames. That risk can be managed by clearing away trees, brush, and grass that would ignite, and replace windows, roofs, and siding with fire-resistant materials.

But a retrofit can run into the tens of thousands of dollars, and whole neighborhoods, especially in suburbs, might end up taking on of the burden, says Erica Fischer, a civil engineer at Oregon State University, who collaborates with Dunn but did not author the new research. “You really have to get buy-in from communities. If your neighbors’ homes are on fire, the probability that your home will ignite is very high.” House fires burn for a long time, showering adjacent properties with embers until the flames are finally put out. The best way to get neighborhood-wide protection, Fischer says, is through mandatory policies like zoning codes, coupled with grants for homeowners.

Fischer points to a bill passed in Oregon last summer as a possible model for protecting people and infrastructure like water, schools, and hospitals from wildfires. Among other things, the legislation creates statewide policies for classifying the fire risk of properties, a bit like flood maps. A state agency is in the process of drafting “defensible space” codes for the highest-risk categories.

That’s not widespread in fire protection, although earthquake and hurricane-resistant building codes are fairly common. “We’ve created mitigation plans for communities for hurricanes, earthquakes, tsunamis, and floods already,” Fischer says. That approach could become more popular: In an interview with the Colorado Sun after the fires outside Boulder at the end of 2021, Colorado Gov. Jared Polis pointed toward the Oregon bill as a possible model.

[Related: Here’s exactly how wildfires are polluting our air]

But the state’s new policy faced resistance from property owners groups, who worried about “farmers … being forced to remove crops near a barn” and other impacts, according to the Oregon Property Owners Association. Local concerns like these will dictate the shape of the national fire response plan. “The pinch points for community protection are likely at a county level,” says Dunn.

Schultz says that communities are slowly warming to the reality that they need to live alongside fire. And according to Ferebee, county officials, sheriffs, and other local policymakers will be attending the Forest Service roundtables that are shaping the crisis plan.

“I think the implication is, your best investments are where you also have partners that are willing to do the work around communities,” says Schultz. If the Forest Service can reintroduce fire and treat forests while nearby communities refit buildings and manage private lands, “that’s what ultimately reduces risk to communities and restores the natural ecological integrity of the forest,” he adds.

That’s how Ferebee says the Forest Service aims to roll out its crisis plan. The first two years will involve projects that are already mapped out; priorities for years three to 10 will be developed with input from community roundtables. If a community says that it doesn’t want to partner on a project, Ferebee says, “we’ll continue to have conversations and work with them until there’s a point in time that they’re either interested and ready, or we’ll just keep working with communities that are interested and ready.” With an estimated 44 million homes at risk of wildfire in the US, there’s likely to be a long line.