A forest containing some of the world’s oldest giant sequoias is threatened by a fast-growing wildfire in California’s Yosemite National Park.
From Friday to Sunday, the fire spread from 250 acres to about 1,600 acres, with the wood and scrub grounds fanning the flames, officials said. Visitors on the Washburn Trail from the Mariposa Grove of Giant Sequoias first reported the fire on July 7, and more than 400 firefighters have gone out to contain it.
The firefighters’ efforts include installing a sprinkler system in the forest to keep the trunks of more than 500 mature giant sequoias moist. Officials also hope the steady spray of sprinkler water will keep flames away from the forest, which they had also previously protected with so-called prescription burns aimed at clearing materials that could help fuel fires.
None of the named trees in the forest — including the 3,000-year-old Grizzly Giant — had sustained significant damage as of Sunday. But the area where firefighters work is difficult and prone to keeping fires burning, especially because of a large number of trees that died in a three-year period from 2013, officials said.
Firefighters narrowly averted disaster on Sunday when debris from the flames nearly hit crew members coordinating ground efforts aboard a plane. Winds swirling around the fire’s column of smoke kicked up the debris, a fire service spokesman told Reuters.
Park managers ordered more than 1,600 visitors to leave from a nearby community, campground and hotel as they prepared for the height of the summer tourist season. They closed off the south entrance to the park as smoke and soot spread from the point of the fire, although visitors can still use the west entrance to access some of the most popular attractions, including Yosemite Valley.

Investigators did not immediately determine the cause of the fire and there were no injuries as a result Monday morning.
The blaze comes after six major wildfires in California’s Sierra Nevada Mountains killed thousands of giant redwoods. In fact, wildfires in that area burned 85% of all giant sequoia groves between 2015 and 2021 — an increase of a quarter in the previous 100 years, National Park Service officials said.
Experts have also warned that the man-made climate crisis is causing droughts that expose redwoods to frequent threats from wildfires.
Reuters and Associated Press contributed coverage