Updated Thursday, July 14, 2022 at 9:15am
A wildfire that threatened a grove of California's giant sequoias in Yosemite National Park burned eastward into the Sierra National Forest on Wednesday.
The Washburn Fire will continue to grow over the next few days, according to a fire update Wednesday night.
“The combination of continued warm and dry weather conditions along with the heavy accumulation of large fuels is creating the perfect recipe for the very active fire behavior we are seeing," the update said.
Firefighting preparations had already been underway in the national forest.
“We've brought in Sierra National Forest folks from the get-go, kind of anticipating that this may happen,” said Nancy Philippe, a fire information spokesperson.
Containment lines within the park, including along the edge of the grove, were holding, firefighting operations official Matt Ahearn said in a video briefing Wednesday.
As of Thursday morning, the fire was 4,375 Acres and 23% contained.
The fire had been entirely within the national park since breaking out July 7, when visitors to the Mariposa Grove of ancient sequoias reported smoke.
Authorities have not said how the fire started and whether it involved a crime or some type of accident.
Park Superintendent Cicely Muldoon told a community meeting this week that it was considered a “human-start fire” because there was no lightning that day.
Philippe said a park ranger who is a trained investigator was on the scene almost immediately when the fire was reported, and a law enforcement team continues to investigate.
Philippe said she believed they had found the point of ignition, but declined to release further information, citing the active investigation.
The fire in the southern portion of Yosemite forced evacuation of hundreds of visitors and residents from the small community of Wawona, but the rest of the park has remained open to summer crowds.
One firefighter suffered a heat injury and recovered, but no structures have been damaged.
Flames mostly skirted the Mariposa Grove, though it did leave its mark on some of the trees. A park forest ecologist credited prescribed burns with protecting the giant sequoias.