Prescribed burns may be one of the best defenses giant sequoias have against today’s extreme wildfires, according to a new University of California, Davis study published in Nature Communications.
The research looked at the 2020 Castle Fire and the 2021 KNP Complex Fire in California’s Sierra Nevada, which killed thousands of giant sequoias. Scientists found that trees exposed to prescribed fire in the previous 10 years were nearly four times more likely to survive than untreated trees nearby.
Lead author Dan Dixon said prescribed burns were effective at lowering sequoia mortality even during severe wildfires. He said that if the goal is to protect giant sequoias, prescribed fire is an essential management tool.
The study used remote sensing data, including airborne lidar and satellite images, to examine fuel conditions and estimate outcomes for about 26,400 giant sequoias across 19 groves. The researchers estimated that earlier prescribed burns may have prevented about 1,900 deaths, and that another 3,900 trees might have survived if all groves had received similar treatment.
According to the study, giant sequoias are naturally adapted to periodic low-intensity fire, but climate change and fire suppression have contributed to more dangerous fuel buildup and more intense wildfire conditions.
