• Rainbow over Half Dome


    National Park California

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  • Road Closures Due to El Portal Fire

    The Big Oak Flat Road between Crane Flat and the El Portal Road is temporarily closed. There is no access to Yosemite Valley via the Big Oak Flat Road or Highway 120. Tioga Road is open and accessible via Big Oak Flat and Tioga Pass Entrances. More »

  • Campground Closures Due to Fire

    Crane Flat, Bridalveil Creek, and Yosemite Creek Campgrounds are temporarily closed. More »

  • Yosemite National Park is Open

    Yosemite Valley, Glacier Point, and Wawona/Mariposa Grove areas are open and accessible via Highways 140 and 41. Tioga Road is not accessible via Highways 140 and 41 due to a fire.

Mechanical Thinning

A Firefighter ignites piles near a park community.

A firefighter ignites piles near a park community under prescribed conditions.

Mechanical Thinning

Mechanical thinning, along with prescribed burning, and wildland fire use fires (WFU) are the three main tools used in the Yosemite Fire Management Program.

Each year, Yosemite does various mechanical treatment projects around park communities to help reduce hazardous fuels near homes and offices. This is done to help create defensible space around structures in the event of an unwanted fire.

This process—known as mechanical thinning—is one tool used by the National Park Service to reduce heavy accumulation of fuels and, ultimately, help prevent larger fires by removing "ladder fuels" that carry fire from the forest floor into the canopy of mature, overstory trees. In turn, this helps preserve natural and cultural resources and provide for public and firefighter safety. These projects also serve to protect park and community structures from larger fires.


Did You Know?

Great gray owl (photo by Cameron Rognan)

In 90 years of serving Yosemite National Park, the Conservancy has seen many accomplishments. From restoring the habitat of the great gray owl to funding the first museum in the Valley, Yosemite Conservancy has played a vital role in the preservation and protection of Yosemite. More...