YOSEMITE NATIONAL PARK, Calif. (AP) — California firefighters gained ground Monday in the battle against a wildfire that threatens a grove of giant sequoias and a small community in Yosemite National Park.

The Washburn Fire on the western flank of the Sierra Nevada had burned about 3.6 square miles (9.3 square kilometers), but was 25% contained by early afternoon, according to an update from the ‘incident.

The fire threatened more than 500 mature redwood trees in the park’s Mariposa Grove and the nearby community of Wawona, which was evacuated.

The area in the southern part of Yosemite was closed to visitors, but the rest of the national park remained open.

Mariposa Grove and Yosemite Valley have been protected since President Abraham Lincoln signed a law in 1864.

A sprinkler system was installed in the grove to maintain humidity, and no serious damage was reported to any named trees, including the 3,000-year-old Grizzly Giant.

“Fortunately, Mariposa Grove has a long history of prescribed burning and studies have shown that these efforts reduce the impacts of unwanted high-severity fires,” a National Park Service statement said.

A heat advisory was issued for the Central Valley stretching below the Sierra while in the fire zone a high temperature of 88 degrees (31 degrees Celsius) was forecast for the village of Wawona, where hundreds of tourists and residents were forced to evacuate last Friday.

“Fortunately, there were no erratic winds which affected the behavior of the fires,” said Marc Peebles, fire information manager. “We have the high pressure that is above the fire causing the temperatures to rise. However, we do get a decent amount of humidity at night which moderates the behavior of the fire allowing our night firefighters to do a good job. »

The giant sequoias, native to only about 70 groves spread along the western slope of the Sierra Nevada, were once considered impervious to flames, but have become increasingly vulnerable to wildfires, fueled by a buildup of undergrowth. century of fire suppression and the impact of drought exacerbated by climate change, have become more intense and destructive.

Lightning-triggered wildfires over the past two years have killed up to a fifth of an estimated 75,000 tall redwoods, which are the largest trees by volume and a major draw for tourists.

There was no obvious natural spark for the fire that broke out Thursday next to the park’s Washburn Trail. Smoke was reported from visitors walking through the grove.

A violent windstorm tore through the grove more than a year ago and toppled 15 giant sequoias, along with countless other trees.

The downed trees, along with a large number of pines killed by bark beetles, provided enough fuel for the flames.

In Utah, smoke and ash from a growing wildfire in rural Tooele County blew through Salt Lake City on Saturday. By Sunday afternoon, the Jacob City Fire had grown to 5.9 square miles (15.3 square km), with zero containment, officials said.

Elsewhere in Utah, firefighters battling high winds battled the 12.4-square-mile (32.2 km2) Halfway Hill Fire in Filmore. Law enforcement arrested four men on Saturday who investigators believe abandoned a campfire that started the blaze.

So far in 2022, more than 35,000 wildfires have burned nearly 4.7 million acres (1.9 million hectares) in the United States, according to the National Interagency Fire Center, well above average for forest fires and acres burned.

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