California wildfires: At least 10,000 giant sequoia trees killed after lightning strikes spark blazes

Wildfires sparked by lightning strikes have killed at least 10,000 giant sequoia trees in California over the past two years - up to nearly a fifth of the world's largest trees.

Officials said fires in Sequoia National Park and the surrounding Sequoia National Forest this year ripped through more than a third of groves in California and scorched an estimated 2,261 to 3,637 sequoias.

Nearby wildlife fires last year killed an unprecedented 7,500 to 10,400 of the giant trees, which are only native to about 70 groves scattered along the western side of the Sierra Nevada range.

The losses account for 13-19% of the 75,000 sequoias greater than 4ft (1.2m) in diameter.

Blazes hot enough to burn and kill sequoias, which were once considered fire-proof, underline the effects of climate change.

A warming planet has produced hotter droughts, fuelling the flames that have killed the ancient trees.

"The sobering reality is that we have seen another huge loss within a finite population of these iconic trees that are irreplaceable in many lifetimes," Clay Jordan, superintendent of Sequoia and Kings Canyon National Parks, told the Associated Press.

"As spectacular as these trees are we really can't take them for granted. To ensure that they're around for our kids and grandkids and great-grandkids, some action is necessary."

California has witnessed its largest fires over the last five years.

Last year set the record for the most acreage burned and this year is running second so far. Large fires burned from August last year into January.

Deaths of the giant trees could have been worse without heavy rain and snow which fell on 25 October, dampening blazes.

Save the Redwoods League, which lost the Waterfall tree - one of the world's largest - in 2020, suffered losses this year in its Red Hill Grove.

"We need to call this situation in the giant sequoia what it is: an emergency," said league President Sam Hodder.

"Just a few years ago, it was considered unprecedented to lose a handful of giant sequoia to wildfire in a season, but now we're losing thousands."