Great article from July 20, but not news to foresters and tribes: “The Bootleg Fire, The Nation’s Biggest, Gives Scientists An Unexpected Experiment.” Excerpts:
Ecologists in a vast region of wetlands and forest in remote Oregon have spent the past decade thinning young trees and using planned fires to try to restore the thick stands of ponderosa to a less fire-prone state.
This week, the nation’s biggest burning wildfire provided them with an unexpected, real-world experiment. As the massive inferno half the size of Rhode Island roared into the Sycan Marsh Preserve, firefighters said the flames jumped less from treetop to treetop and instead returned to the ground, where they were easier to fight, moved more slowly and did less damage to the overall forest.
The initial assessment suggests that the many years of forest treatments worked, said Pete Caligiuri, Oregon forest program director for The Nature Conservancy, which runs the research at the preserve.
“Generally speaking, what firefighters were reporting on the ground is that when the fire came into those areas that had been thinned … it had significantly less impact.”
The reports were bittersweet for researchers, who still saw nearly 20 square miles of the preserve burn, but the findings add to a growing body of research about how to make wildfires less explosive by thinning undergrowth and allowing forests to burn periodically — as they naturally would do — instead of snuffing out every flame.
Historically, wildfires in Oregon and elsewhere in the U.S. West burned an area as big or bigger than the current blaze more frequently but much less explosively. Periodic, naturally occurring fire cleared out the undergrowth and smaller trees that cause today’s fires to burn so dangerously.
Those fires have not been allowed to burn for the past 120 years, said James Johnston, a researcher with Oregon State University’s College of Forestry who studies historical wildfires.
The area on the northeastern flank of the Bootleg Fire is in the ancestral homeland of the Klamath Tribes, which have used intentional, managed fire to keep the fuel load low and prevent such explosive blazes. Scientists at the Sycan Marsh research station now work with the tribe and draw on that knowledge.
This refutes some of Chad Hanson’s claims in his new book, Smokescreen, which we discussed here:
“Thinned forests often burn more intensely in wildland fires,” [Hanson] writes, “because thinning reduces the windbreak effect of denser forests, allowing winds to sweep through more rapidly, while also reducing the shade of the forest canopy and creating hotter and drier conditions.”
There may be some situations where fuels, weather, and topography can allow this to happen, but “a growing body of research” shows that reducing fuels and thinning works. I’m glad the NPR article mentioned the role of the tribe’s knowledge and practices.