Devastating megafires are becoming more common, owing in part to global warming.
A new study suggested that reintroducing "good fire" to the United States and other wildfire-prone areas, as Native Americans once did, could potentially mitigate the role of climate in triggering today's wildfires.
Indigenous tribes buffered climate's impact on wildfires
For roughly 400 years in the southwestern United States, the age-old Native American tradition of "cultural burning" appears to have previously weakened - though not eliminated - the link between climate conditions and fire activity, as per ScienceDaily.
SMU fire anthropologist Christopher Roos and colleagues discovered that the typical climate-fire pattern from 1500 to 1900 reflected one to three years of above-average rainfall (allowing vegetation to grow) followed by a fire-fueling year of significant drought by studying a network of 4,824 fire-scarred trees in Arizona and New Mexico, where the Apache, Navajo, and Jemez tribes lived.
According to the group's study published in Science Advances, the pattern was broken when Native American tribes performed traditional burning practices.
"What's remarkable is that the impact of Native American fire management was visible across hundreds of square kilometers," said Roos, the study's lead author. "That extends over entire mountain ranges."
According to Roos, the findings suggested that we can learn from Native Americans how to be less vulnerable to the current fires.
Four of the study's co-authors are tribal members who assisted with representing their people's culture and history and interpreting the fire data.
Many Native American tribes in the US Southwest have held controlled burns of small trees, grasses, and shrubs at regular intervals for millennia to clear out underbrush and encourage new plant growth.
According to Roos, the patchwork of small, deliberate burns also removed much of the fuel that could burn in wildfires, which could explain the break in the climate-fire pattern.
The researchers used a variety of methods, including interviews with tribal members in each community, to document how these tribes dealt with smoke and fire centuries ago.
The researchers also compared tree-ring fire records to paleoclimate data.
Scientists use tree rings to determine the age of a tree and the wet and dry weather patterns of moisture and drought.
Similarly, scarring on tree rings, which dates the occurrence of fires, is scientists' best evidence for fire activity.
Roos and his colleagues obtained their ancient tree-ring data from the North American Fire Network's International Multiproxy Paleofire Database.
The investigation concentrated on dry coniferous forests in New Mexico and Arizona.
Many indigenous tribes relied on cultural burning.
The Apache, Navajo, and Jemez tribes all relied on fire, as per Eurasia Review.
The Apache tribe lived from central Arizona to Texas, but the researchers concentrated on residents who lived in southeastern Arizona between the 1500s and 1900s.
The Apache people primarily used fire to gather, garden, and hunt, sometimes setting fires to attract deer and elk to specific locations.
The Navajo people lived in small, family-based communities on the northern border of Arizona and New Mexico, where they raised sheep, hunted, gathered, and gardened.
According to research, Navajo pastoralism reduced fire activity in pine forests, but burning practices may also have kept fires burning frequently in heavily traveled areas.
The Jemez were farmers and hunters who lived in northern New Mexico's Jemez Mountains. Previous research has found that they purposefully burned small patches of forest around their community, limiting fire spread and improving forest resilience to climate variability.