Dec 7, 2022 - Energy & Environment

Ancient Indigenous practice could curtail today's wildfires

A plume of smoke envelops a stand of trees in a forest.

Photo: Brent Johnson, NPS

A study published Wednesday in the journal Science Advances found that historical Indigenous "cultural burning" curtailed wildfire patterns on local scales over a period of roughly 400 years in the southwestern U.S.

Driving the news: As warming temperatures drive the risk of increased and intensified wildfires across the world, adapting traditional burning practices into fire management could diminish the role of climate in enkindling today’s wildfires.

Details: The study looked at tree-ring records of 4,824 fire-scarred trees in dry pine forests in Arizona and New Mexico.

  • It mapped out the climate impact of small-scale controlled burns between 1500 to 1900 in parts of the traditional homelands for the Ndée (Apache), the Diné (Navajo), and the Hemish (Jemez) Indigenous peoples.
  • By comparing tree-ring fire records with paleoclimate records and interviewing Indigenous descendent communities, researchers assessed how tribes handled wildfire centuries ago — with the aim to figure out the geographic scale of impact of Indigenous fire management.
  • "People can really learn from this," says Chris Toya, a Tribal Historic Preservation Officer and a member of the Pueblo of Jemez, who co-authored the study.
  • Toya noted that interviewing Indigenous elders provided insights into the ancestral practice that researchers wouldn't have found otherwise. "It shows that connection that our ancestors had to their homeland."

Flashback: Between 1500 and 1900, Indigenous tribes in the southwestern U.S. regularly burned grasses, small trees and vegetation to clear out debris, invite plant growth and utilize more land for farming, Toya tells Axios.

  • That practice removed much of the fuel that could burn in wildfires, researchers say.

What they found: In past periods of intensive cultural burning, most of the stands of trees researchers looked at lacked any significant fire-climate patterns. They view that as evidence of the Indigenous fire management itself diminishing the relationship between climate and fire.

  • "Our ancestors really knew the landscape. They were confident in burning the areas that they wanted to burn, because they saw in the future that it will benefit, not only themselves, but everything in the environment," said Toya.

Yes, but: The impacts were localized — meaning these strategies were found to lessen climate conditions that drive wildfires on smaller geographic scales and landscapes, but not broader, regional ones.

  • In order to see wider benefits of this, Chris Roos, lead author of the study, tells Axios that fire management programs would need to operate "with lots and lots of local burns across the entire region at the same time," matching frequencies once or twice a decade.
  • "This suggests that that type of burning can really reduce the vulnerability of these places to climate influences," says Roos, a fire anthropologist at Southern Methodist University.

The bottom line: The new study suggests that restoring and adapting Indigenous burning practices can influence certain climate conditions — which, if incorporated into local management strategies, its authors say could lessen the susceptibility of the landscape to wildfires across the Southwest.

  • "This is exactly the kind of benefit that Jemez and Navajo and Apache folks benefited from for centuries," Roos tells Axios.
Go deeper