California’s biggest fire is burning a desert — and Joshua trees

California – The state’s biggest fire in 2023 is torching a place that, until recently, rarely burned: the high desert, where plant coverage is sparse.

And the flames this week are tearing through one of the planet’s only habitats for the Joshua tree, an icon of the American West.

The plant, known for its thin, twisting limbs and spiky leaves, lives at only specific elevations in the Mojave Desert, its range limited to a handful of south-western states.

The York Fire erupted on Friday in the Mojave National Preserve and has now scorched 33,346ha straddling the Nevada border, burning an unknown number of Joshua trees in the process. 

The trees – a type of yucca – are not adapted to withstand wildfires, which used to be rare in the desert.

But invasive grasses have been spreading across the Mojave in recent years, providing fuel – especially after wet winters like California experienced in 2023.

And Joshua trees already face a perilous future, as climate change is expected to shrink their range, making the Mojave hotter than they can stand.

Urban development and solar power plants proliferating across the desert also nibble away at their habitat. 

“Things are really bad, and fire isn’t the only thing,” said Professor Christopher Smith, a biology professor at Willamette University in Oregon, who is studying the tree’s genome. “They’re seeing threats from all sides.”

It is not the only emblematic California tree endangered by fire and a warming world.

The last decade of high-intensity fires in the state’s Sierra Nevada Mountains have devastated giant sequoias, immense trees found nowhere else.

One fire alone – 2020’s Castle Fire – killed an estimated 10 per cent to 14 per cent of all large sequoias in existence, according to the National Park Service. 

Fire sparked by a lightning strike tore through another portion of the Mojave National Preserve just three years ago, killing an estimated 1.3 million Joshua trees.

The cause of the York Fire remains under investigation, and the blaze was 30 per cent contained Wednesday morning. 

California has, until now, enjoyed a relatively quiet fire season, following last winter’s intense rain, snow and flooding.

So far, wildfires have burned almost 38,850ha compared with the five-year average of 142,044ha by this date, according to the California Department of Forestry and Fire Protection.

But the abundance of grasses that grew in the wake of the rains could lead to larger fires this autumn, as the state’s annual dry season reaches its peak. Bloomberg