California can use fire to kill wildfire
A crew member monitors a prescribed burn at Yosemite National Park on October 18, 2008. Fire helps recycle important nutrients back into the soil and makes way for new grasses, wildflowers and other plants.
If California wants to get out in front of its wildfire problem, scientists have some clear but counterintuitive advice: Start more forest fires. Decades of research shows that lighting fires under safe conditions not only clears out the dead plants and thick underbrush that fuel many severe wildfires, it also restores a natural process that once kept forests healthy and resilient.
It can be tricky to pull off because all fires, whether natural or intentional, are inherently dangerous and smoky. Even so, experts say the benefits far outweigh the risks.
California’s overgrown forests came under scrutiny when President Donald Trump blamed them for the state’s recent fires and called for more aggressive management.
Experts say the diagnosis was misplaced; the fires in both Paradise and Southern California drew their deadly power from extreme weather conditions exacerbated by climate change, not from the buildup of dense trees and brush.
Nevertheless, scientists and land managers agree on the importance of reducing flammable fuel in California’s vast conifer forests. And they say that fire is the best tool for the job.
“We really have to understand that what’s really needed on the landscape is more fire, not less,” said Kelly Martin, the fire chief of Yosemite National Park.
Some fires will happen no matter what, scientists say. The question is: Do we want fires we can control, or fires we can’t?
Until the 1800s, when settlers flooded into California, many parts of the state experienced far more wildfire than they do today. Natural fires burned unimpeded, and Native Americans lit blazes to reduce future risks and boost the growth of desirable plants, as they had done for thousands of years. The state’s ecosystems evolved not just to tolerate burning, but to depend on it.
“California landscapes were really truly born and bred of fire,” Martin said.
Then the federal government intervened. After several massive wildfires ripped through the West in the early 1900s, the newly formed US Forest Service began extinguishing flames as quickly as possible. Managers believed that suppressing fires protected both communities and forests, Martin said. And for decades, it did.
But over time, the plan backfired. That was especially true in conifer forests, which used to burn every five to 20 years and grew denser with each missed cycle.
Then came drought, tree-killing beetles and climate change – plus a booming population that kept expanding into forested areas.
Californians are all too familiar with the consequences: catastrophic wildfires that are nearly impossible to contain.
“If you want to really, fully restore the forest, you have to get fire back in there,” said Malcolm North, a research scientist at the US Forest Service’s Pacific Southwest Research Station in Davis, Calif.
Beyond removing saplings and pine duff, fire creates natural variability in the spacing of trees, he said. It typically leaves denser stands in wetter places and creates gaps in dryer areas that prevent flames from spreading.
“That’s one of the features which made forests so resilient to fire and drought,” he said.
Fire also plays a critical role in breaking down material on the forest floor and recycling nutrients.
Except near communities, the goal of prescribed burns is not to prevent future fires, but to allow more wildfires to burn safely, North said.
The 2013 Rim fire was a prime example.
It started with a runaway campfire on National Forest land east of Groveland, Calif., and quickly metastasised. But then it spread into nearby Yosemite National Park, where for decades Martin and her predecessors had been lighting prescribed fires and allowing natural ones to burn.
When the Rim fire hit previously treated areas, it suddenly became tamer. It dropped from the canopy back down to the ground, burned less intensely, and didn’t require much suppression, Martin said.
The controlled burns also protected staff buildings near the Hodgdon Meadow Campground. “We didn’t lose any homes,” she said.
Despite its effectiveness, prescribed burning remains vastly underutilised in California and across the West.