MISE À DAY
A massive fire at California's prestigious Yosemite Park last week has spared its iconic giant sequoias, authorities said.
The fire dubbed the “Washburn Fire” broke out on July 7 for an as yet undetermined reason and quickly reached the Mariposa Grove area, one of the most popular places in the park because it contains hundreds of the most important redwoods. great in the world.
The protective measures implemented by several hundred firefighters bore fruit and the venerable trees were no longer immediately threatened by Thursday morning.
“I did not see a single tree that was dead or damaged. 'wasn't going to survive,' Garrett Dickman, a Yosemite National Park ecologist who has surveyed Mariposa Grove every day since the blaze began, told NBC television Wednesday night.
A team of firefighters had in particular permanently sprinkled the area surrounding the “Grizzly Giant” – the most famous and most spectacular giant sequoia in the park with 64 m in height – to prevent the flames from taking hold.
In addition to these precautions, preventive measures have been taken on a regular basis in recent years, such as controlled fire starts to clear brush and reduce the risk of violent fires.
“I think the most important effort has been to organize fires in the Mariposa Grove since the 1970s. Fifty years of reducing fuels is what will ultimately protect the trees” , underlined Mr. Dickman.
Practiced in an ancestral way by the Native American tribes of the region, the controlled fires are intended to clear up the undergrowth by consuming brush and dead trunks fallen on the ground. These fuels can greatly increase the intensity of wildfires, especially in times of chronic drought such as the one currently affecting the American West.
“Almost every tree was lucky enough to be exposed to low-intensity fire (…) The threat has almost completely disappeared,” Stanley Bercovitz, spokesman for the United Nations Forestry Office, told AFP. United States.
“Until the fire is 100% contained, there is always a risk. But currently it is greatly reduced and the fire is moving away from the redwoods,” he added.
The fire was heading towards the Sierra National Forest, further east, on Thursday.
Thursday morning, it was 23% contained and had covered nearly 1800 hectares of vegetation.
Low intensity fires are generally not enough to harm giant sequoias, naturally adapted to these disasters with their spongy and thick bark and first branches that can grow thirty meters high, out of reach of the flames.
On the contrary, these sequoias need fires to reproduce: the heat of the flames causes the fallen cones to pop like popcorn to release hundreds of seeds.