Prescribed Burns and Forest Thinning Averted Millions of Tons of Emissions and Billions in Damages

Work to reduce excess flammable vegetation in forests warded off the release of 2.7 million tons of carbon dioxide, averted nearly 60 premature deaths and avoided $2.8 billion in damages in the Western U.S., according to a new study from the University of California, Davis. 

The study, published May 7 in the journal Science, also found forest fuel treatments—prescribed burns and mechanical forest thinning operations—during a six-year span prevented more than 25,000 tons of fine particle pollution from being released into the air.

The research was supported by the U.S. Forest Service and the University of California’s Giannini Foundation for Agricultural Economics.

The findings come as weather forecasters and first response agencies predict an extremely active wildfire season across the West, with record-low snowpack, drought-stricken lands, extreme heat and the ever-looming threat of windy conditions. As of May 8, more than 25,000 wildfires had burned over 1.8 million acres nationwide, well above the 10-year average for acreage burned to that date, according to the National Interagency Fire Center.

“There’s been a lot of ecological research that has been done on fuels management, but there’s been less so on the economic side,” said the study’s lead author Frederik Strabo, an assistant professor in the Department of Resource Economics and Environmental Sociology at the University of Alberta and a postdoctoral scholar at UC Davis’s Department of Agricultural and Resource Economics.

Strabo called the latest research “a step forward” for wildfire science and preparation for major incidents. 

The UC Davis study focused on 285 wildfires throughout 11 Western U.S. states due to the large-scale and severity of wildfires across the region. The researchers found that every dollar invested in fuel treatments translated to $3.73 in expected benefits.

“This is amazing,” John Battles, a professor and chair of forestry and sustainability at the University of California, Berkeley, said after reviewing the study. Battles, who has been on an advisory panel for the governor-created California Wildfire & Forest Resilience Task Force for the last eight years, was not involved in the UC Davis study.

“It’s not a half-baked conclusion,” said Battles. “There’s really strong statistics behind their methodology.

“What I’m seeing here in this big aggregate totally fits with (the) more place-based analysis, where we look at these treatments, we track them over time, and we see their other benefits change,” he said.

The wildfires studied took place between 2017 and 2023 in areas where those incidents interacted with U.S. Forest Service fuel treatments. These years were chosen in part based on available federal data.

Fuel treatments include prescribed burns—blazes planned and intentionally set to burn away dangerous accumulations of flammable vegetation—biomass removal, like forest thinning operations with chainsaws, axes and heavy machinery, and a combination of the two strategies. 

Battles said prescribed fires are often the most effective strategy to fend off wildfires, but also the trickiest to carry out. “It’s challenging,” he said. “It produces emissions. You always have the risk of escape. A lot of folks don’t want to have a fire right near their houses.”

Short-­term fire suppression by state and local agencies is often favored over long-­term prevention because immediate response is more visible and “politically safer,” the study’s authors noted.

Regardless, Battles said prescribed fires, biomass removal and a combination of those practices will be important not only to implement now but to expand going forward. 

The UC Davis study concluded the same.

The U.S. Forest Service vowed to treat more than 50 million acres of forest over the next decade in the 2022 update to its “Wildfire Crisis Strategy,” which outlined ways to be proactive in confronting conflagrations of increasing size and destructiveness. That acreage is about the size of Utah. 

UC Davis experts noted that fuel treatment for the fires analyzed reduced the total burn area by about 152,000 acres, compared to a scenario without that preventative work. 

“These treatments remain underutilized, in part because public pressure and risk aversion skew wildfire management resources toward fire suppression rather than prevention,” they wrote in a research article about the study. 

UC Davis researchers wrote in the study that evidence—like research published in Advancing Earth and Space Sciences and Frontiers—suggests potential costs from fuel treatments “are generally lower than would be experienced in the absence of treatment.” 

“Wildfires produce about 83 percent more fine particulate matter than prescribed burns over the same area,” according to the U.S. Forest Service.

In its latest State of the Air report, the American Lung Association, highlighted that nearly half the children in the U.S. live in places with dangerous levels of air pollution. Extreme heat and wildfires—worsened by human-made climate change—are helping to reverse decades of air quality improvements following the passage of the Clean Air Act in 1970. 

“We support prescribed fires—under certain conditions—as a tool to reduce wildfire risk,” Will Barrett, the assistant vice president for nationwide clean air policy at the American Lung Association, said. The ALA was also not involved in the UC Davis study.

Prescribed burns “need to be planned,” Barrett continued, “and carefully managed to limit smoke exposures that might follow at the same time.”

Controlled burns offer upsides that wildfires don’t. Municipalities know what will burn and thus what emissions could be released, Barrett said. Agencies can also warn residents about fuel treatments ahead of time. 

Strabo, who led the UC Davis study, had ideas for additional research to help the U.S. prepare for wildfires expected to burn increasing amounts of land. 

Those ideas ran the gamut: What are the most effective ways to prepare land for wildfires in various states? What actionable advice can be given to land managers? How much treatment needs to be done on a landscape to prepare it for a potential major wildfire? What makes the most sense from an economic standpoint while preparing for wildfires in the long term?

All will be vital to consider as swaths of the country hunker down for what may be a particularly perilous fire year and a new era for massive wildfires, said Battles.

“The biggest threat certainly in California and much of the American West is high-severity wildfires,” Battles said, “and it has all these knock-on effects. … We have to get a handle on the wildfire crisis and it has to be done at scale.”