Western US Forests Need More Managed Fires

Controlled burns can mitigate future wildfire severity. Wikimedia

For much of the last century, wildfire policy in the western United States has focused on limiting or suppressing burned areas while declining to thin or control forest overgrowth and old, dry wood.

A recent analysis presented at the American Geophysical Union (AGU) reveals that many western US ecosystems are now experiencing a profound “fire deficit”—meaning the environment has gone far longer without fire than natural historical patterns suggest. According to the study, restoring environmental health will require burning almost 4 million acres a year through a combination of natural fires and prescribed burns.

“Conditions are getting so warm and dry that it’s causing huge amounts of fire compared to the historical record,” said Winslow Hansen, director of the Western Fire and Forest Resilience Collaborative and a scientist at the Cary Institute of Ecosystem Studies, in the AGU press release. “However, we still are dealing with the legacy of 150 years of fire suppression. Together, drying conditions and overly dense fuels portend a challenging and more fiery future.”

Key Data Points from the Study

• Nearly 74% of the western United States is in a fire deficit, meaning these landscapes have experienced significantly less fire than expected, based on historical fire return intervals.

• Approximately 38 million hectares (94 million acres) of land across the western US are overdue for fire.

• This ecological imbalance is the result of long-term fire suppression, which has contributed to uncontrolled buildup of dense vegetation and tinder.

• To eliminate the fire deficit over the next decade, about 3.8 million hectares per year would need to burn.

• That is roughly three times the area burned during the record 2020 wildfire season.

Why It Matters

The study reframes wildfire risk in the western US not simply as a consequence of climate change or extreme weather but as the result of inadequate forest management. Even current natural wildfire activity is insufficient to restore historical fire regimes.

Without proactive strategies—such as prescribed burning and landscape-scale management of flammable tinder—the growing fire deficit may continue to drive increasingly severe and uncontrollable wildfires, with consequences for biodiversity, carbon storage, air quality, and human communities.

Source:

• American Geophysical Union press release, “Nearly three-quarters of western U.S. overdue for wildfires”