A forest ecologist said Tuesday a grove of giant sequoias in Yosemite National Park survived its first wildfire in more than 100 years because of intentional fires used to burn the undergrowth beneath the trees.
Garrett Dickman, who toured the forest, said small fires that had been lit on purpose over the past 50 years essentially saved the sequoias, stopping the fire when it reached the trees and allowing firefighters to prevent flames from doing further damage than charring bark.
"We’ve been preparing for the Washburn Fire for decades," Dickman, who works for the park, said. "It really just died as soon as it hit the grove."
The fire started Thursday near the grove and had burned 5 square miles on Tuesday. However, it was 22% contained and was moving away from the park's largest grove of sequoias.
The flames, which started near a trail, were not caused by lightning, authorities said. The authorities would not say whether the fire was lit accidentally, intentionally or as a result of negligence.
Hundreds of people had to be evacuated from the nearby community of Wawona on Friday, and the grove and southern entrance of the park were both closed due to the blaze. The remainder of the park was left open.
Some sequoias were charred by the fire, which reached 70 feet up their trunks. Dickman said he toured the grove and did not believe any of the trees would die.
The Galen Clark tree, a large tree at the top of the grove, was one of the few named trees that were burned. The tree was named after the park's first guardian.
"It got a little bit of heat," Dickman said. "But from the pictures I’ve seen, it, too, is gonna survive."
The preventative fires mimic low intensity that aid the sequoias by clearing out downed branches, flammable needles and smaller trees that could take up their light and water. The last intentional fire was conducted in 2018.
The intentional burns have been utilized on sequoias for more than 60 years, but have more recently been viewed as a necessity to the save the trees. Up to 20% of all giant sequoias have died in the past five years during intense wildfires.
Dickman said this is the first time the Mariposa Gove had been victim to a wildfire in more than a century, although several large blazes have come close in the past 10 years.
The Associated Press contributed to this report.