Giant Sequoia trees are the largest known living organisms on the planet and may be among the most resilient, too. Hundreds of feet tall, they can live for over 3,000 years.
And with their thick bark, they've also evolved to withstand most forest fires.
But the devastating wildfires that swept through California in recent years are proving too much for some to handle. One blaze in September killed dozens of Sequoias, part of a worrying trend.
Garrett Dickman is a botanist from Yosemite National Park:
"It's really alarming to me that we're losing Giant Sequoias because if there's a tree that can handle fire, this is that tree and that we're losing them, it's beyond all expectations."
"The idea of national parks was born out of Giant Sequoias and protecting them. It's something Californians recognize [audio briefly mute] as part of their identity."
Fire crews in California have resorted to wrapping the base of General Sherman, the world's largest tree, in aluminum material to protect it.
One of the trees' weaknesses is their crown. If fire reaches the those upper branches it can be fatal.
"Right here is the line left behind by the smoke jumpers in case they need to get back in the tree. This goes all the way to the top of the tree and the climbers climb the line and brought a hose up with them and there was a hole in the top of the tree where there was smoke and flames that was coming out of that and they brought the hose all the way to the top, stuck it into that hole and they were able to put the fire out from the top of it and prevented that hole from burning further and further and deeper into that tree. "
For Dickman, the Giant Sequoias meant a lot more than its ecological importance.
"It's part of Americans and it's part of their identity and I think big trees everywhere, the whole world identifies with this tree and so it's something that I think everyone in the world can appreciate and love and enjoy so yes, they are important ecologically but it's what this tree means to us."