A wildfire in Yosemite threatens the redwoods of Maripas Grove

WAVONA, Calif. — Yosemite National Park’s largest grove of giant sequoias remained closed Saturday as firefighters battled a blaze that threatened to harvest the iconic trees and forced hundreds of hikers to evacuate.

The rest of the park in California remained open, although the smoke hanging in the air obscured some of the most scenic views and vistas.

More than 500 mature sequoias are threatened in Maripas Grove, but as of Saturday afternoon there were no reports of serious damage to any of the trees, including the 3,000-year-old Grizzly Giant. Some of the massive barrels were wrapped in fireproofing for protection when the flames got out of control.

The cause of the fire is being investigated.

Beyond the trees, the small community of Wawona, surrounded by a park and campground, was under threat, with people ordered to leave their homes and campsites Friday night.

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The fire proved difficult to contain, and firefighters used “every possible tactic” against it, said Nancy Phillip, spokeswoman for Yosemite Fire Information. That included aerial drops of fire retardant as well as the planned use of bulldozers to build fire lines, a tactic rarely used in a desert like Yosemite, Phillip said.

Bulldozers will primarily be used to erect fire lines to protect Wawona, she said. About 600 to 700 people who were staying in tents, cabins and a historic hotel at Wawona Campground were ordered to evacuate.

Although firefighters encountered hot and dry conditions, they did not have to contend with strong winds Saturday, said Jeffrey Barlow, senior meteorologist for the National Weather Service in Hanford. Given the fire’s relatively small size and minimal wind, the effects of the smoke were not expected to spread far beyond the park, he said.

The giant sequoias, which grow in just 70 groves along the western slope of California’s Sierra Nevada range, were once thought to be impervious to flames, but have become increasingly vulnerable as wildfires are fueled by the accumulation of undergrowth as a result of a century of fire suppression and drought-increasing changes climate have become more intense and destructive.

Forest fires caused by lightning have killed up to one-fifth of the approximately 75,000 big redwoods, the largest trees by volume, in the past two years.

There was no apparent natural spark for the fire that broke out Thursday near Washburn Trail in the park, Phillip said. The smoke was reported by visitors playing in the grove, which reopened in 2018 after a $40 million renovation that took three years.

By Saturday evening, the fire had spread to about 1.9 square miles.

A year and a half ago, a fierce wind swept through the grove and felled 15 giant sequoias along with countless other trees.

The fallen trees, along with a large number of pine trees killed by bark beetles, provided ample fuel for the fire.

The park used prescribed burns to clear brush around the redwoods, which helps protect them if the flames spread further into the grove.

Meanwhile, most evacuation orders were lifted Saturday in the Sierra foothills about 80 miles northwest of the Yosemite fire that started on July 4. The Electra Fire, which started near Jackson, was largely contained, and only areas immediately within the Perimeter fire zone remained under evacuation orders, according to the California Department of Forestry and Fire Protection.