Yosemite National Park's aggressive initial attack response on the Washburn Fire

A firefighter walks along a road at night beside flames engulfing vegetation.
A firefighter walks down a firebreak on the Washburn Fire in Yosemite National Park.


During the Civil War in 1864, President Abraham Lincoln signed legislation protecting the Mariposa Grove of Giant Sequoias and Yosemite Valley. For the first time in history, land was set aside to be protected and enjoyed by future generations and the idea of the national park system stemmed from this legislation.

The Mariposa Grove is the largest of three groves in Yosemite National Park and has approximately 580 giant sequoias. Giant sequoias are among the world’s largest and longest-lived trees, reaching 2,500-3,000 years old. They are a fire-adapted species that grow naturally only in the California Sierra Nevada mountain range. Historically, fire rarely killed mature giant sequoias. However, approximately 20% of giant sequoias have been lost in recent years due to high severity fires.

Firefighters stand in front of a giant sequoia tree with a cavity at the bottom.
Resource Advisors assigned to the Washburn Fire in Yosemite National Park.


When 911 callers reported a wildfire near the Mariposa Grove on July 7, 2022, a full suppression response was immediately launched. Yosemite’s helicopter 551, multiple wildland fire engines, and firefighters responded to the Washburn Trail near the Mariposa Grove. An immediate evacuation of over 450 visitors in the grove occurred using local shuttle buses. As the fire continued to grow, additional resources including air tankers, helicopters, as well as ground resources including a Type 2 incident management team, hotshot crews, and engines were requested. Over 1,700 responders included federal, state, local and Tribal personnel from across the nation assisted with suppression.

Due to the threat, a mandatory evacuation of 1,600 visitors, residents, and employees was declared for the community of Wawona, including the historic Wawona Hotel. On July 13, 2022, the fire burned onto the neighboring Sierra National Forest. Coordination with Sierra National Forest staff and suppression strategies were in place from the beginning in the event the fire spread to US Forest Service lands.

Firefighters gather near a tree with firefighting gear and packs spread around them.
Crew assembles gear during the Washburn Fire.


The Washburn Fire was fully contained on August 3, 2022, at 4,886 acres. The cause remains under investigation. Due to the aggressive suppression efforts and the history of ongoing fuel treatments dating back to the 1970s, no loss of giant sequoias or structures occurred. Fuel reduction treatments and prescribed burns will continue to be conducted in the giant sequoia groves to protect the trees from future wildfires. Studies of fuels, fire effects, beetles, and climate stress are ongoing to better understand the association between changing environmental conditions and long-term persistence of giant sequoias. Full fire suppression responses in the groves will continue so future generations can experience the majesty of the world’s largest trees.

Yosemite National Park

Last updated: December 1, 2022