California Fires Seen Killing Up to 20% of World’s Sequoias

(Bloomberg) -- California wildfires have killed up to one-fifth of the world’s total population of giant sequoias in the past two years with thousands torched by blazes this summer, federal park officials said. 

The KNP and Windy Fire, which tore through the Sequoia and Kings Canyon National Parks earlier this year, have already destroyed or will eventually kill between 2,261 and 3,637 large sequoias, or 3% to 5% of the world’s total, according to a report published Friday by the National Park Service.  

Those losses come after as many as 10,600 large sequoias, or up to 14% of a total of about 75,000 trees, were lost in the 2020 Castle fire, officials said.  

The 2021 tree deaths are “significant, unsustainable and outside the range of historic fire facts on large sequoias,” said Christy Brigham, co-author of the report and chief of resources management at Sequoia and Kings Canyon National Parks, during a media event Friday. 

“A combination of fire exclusion in many areas for over a century combined with climate change driven hotter droughts have increased fuel loads and changed fire behavior beyond what these incredibly fire-adaptive trees can tolerate,” Brigham said. 

California suffered through another severe wildfire season that destroyed thousands of structures and forced thousands to evacuate, including from the mountain resort town of South Lake Tahoe. A severe drought left the state’s forests and hilly grasslands primed to burn. More than 3 million acres were torched, according to the California Department of Forestry and Fire Protection. 

Giant sequoias are the largest trees in the world, with trunk circumferences as much as 100 feet (30 meters). They can live for thousands of years. The parks boast several groves of the ancient giants, including the largest tree on Earth by volume. 

In Sequoia National Park, home to the ancient Giant Forest, firefighters had wrapped some of the majestic trees in protective foil to protect them as the flames approached. Sequoias have adapted to live with periodic fires as their thick bark can protect them from flames, while forest blazes prepare the soil for sequoia seeds to germinate. 

However, prolonged severe droughts, which scientists say may become more common with climate change, and massive blazes, have threatened the species.

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