Fire crews struggle to contain Washburn Fire burning in Yosemite
YOSEMITE NATIONAL PARK (CBS SF/AP) - A wildfire that has been threatening a grove of giant sequoias in Yosemite National Park appears to be burning away from the ancient trees Wednesday as crews struggled with containment.
The Washburn Fire that started almost a week ago near the park's Mariposa Grove had burned 3,772 acres as of Wednesday morning. Containment was up to 22% on Tuesday, but officials reported a decrease to 17% on Wednesday.
However, firefighters said the flames were moving away from the largest grove of sequoias in the park and eastward into the Sierra National Forest on Wednesday. Based on prevailing winds, it was unlikely to return to the grove.
The cause of the fire was under investigation.
The fire was proving difficult to contain, with firefighters throwing "every tactic imaginable" at it, said Nancy Phillipe, a Yosemite fire information spokesperson. That included air drops of fire retardant as well as the planned use of bulldozers to create fire lines, a tactic that's rarely used in a wilderness setting like Yosemite, Phillipe 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," Philippe said.
Containment lines within the park, including along the edge of the grove, were holding, firefighting operations official Matt Ahearn said in a video briefing.
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.
About 600 to 700 people who were staying at the Wawona campground in tents, cabins and an historic hotel were ordered to leave on Friday.
On Tuesday, Sacramento affiliate CBS 13 reported that a forest ecologist who toured the Mariposa Grove said the giant sequoias had survived their first wildfire in more than a century, largely thanks to efforts to regularly burn the undergrowth beneath the towering trees.
Small, intentionally lit fires over the past 50 years essentially stopped the fire in its tracks when it hit the Mariposa Grove and allowed firefighters to stand their ground and prevent flames from doing more than charring the thick bark on the world's largest trees, Garrett Dickman said.
"We've been preparing for the Washburn Fire for decades," said Dickman, who works for the park. "It really just died as soon as it hit the grove."
Some of the sequoias were charred by flames that reached 70 feet up their trunks, but Dickman said he surveyed the grove and did not think any of the trees would die. The Galen Clark tree, a large tree at the top of the grove named for the park's first guardian, was one of the few named trees that burned.
"It got a little bit of heat," Dickman said. "But from the pictures I've seen it, too, is gonna survive."
The giant sequoias, native in only about 70 groves spread along the western slope of California's Sierra Nevada range, were once considered impervious to flames but have become increasingly vulnerable as wildfires fueled by a buildup of undergrowth from a century of fire suppression and drought exacerbated by climate change have become more intense and destructive.
Lightning-sparked wildfires over the past two years have killed up to a fifth of the estimated 75,000 large sequoias, which are the biggest trees by volume.
There was no obvious natural spark for the fire that broke out Thursday next to the park's Washburn Trail, Phillipe said. Smoke was reported by visitors walking in the grove that reopened in 2018 after a $40 million renovation that took three years.
The downed trees, along with massive numbers of pines killed by bark beetles, provided ample fuel for the flames.
The park has used prescribed burns to clear brush around the sequoias, which helps protect them if flames spread farther into the grove.
