As It Happens·Q & A

Standing by world's largest tree gives 'feeling of eternity' says woman trying to save it from fire

So far, the colossal giant sequoia known as the General Sherman hasn't been harmed by ongoing wildfires, thanks to the efforts of California firefighters who wrapped the tree's base in aluminum blankets and cleared vegetation from around it.

'You can really feel its age and size and presence' says Christy Brigham, of the General Sherman sequoia

Firefighters wrap the General Sherman tree, the largest tree on earth by volume, in fire-resistant blankets. The tree stands 84 metres tall in the Giant Forest, a section of Sequoia National Park in Calif. that is home to several of the world's biggest trees. (Sequoia & Kings Canyon National Parks)

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So far, the colossal giant sequoia known as the General Sherman hasn't been harmed by ongoing wildfires, thanks to the efforts of California firefighters who wrapped the tree's base in aluminum blankets and cleared vegetation from around it.

"It's just an extra layer of protection for this tree that is so important to all of us," said Christy Brigham, the chief of resources management and science for Sequoia and Kings Canyon National Parks in California.

The General Sherman tree is located in Sequoia National Park's Giant Forest sequoia grove, which is home to some of the largest trees in the world. The forest is being threatened by the KNP Complex fire, which was the result of two wildfires merging into one, spread across 9,600 hectares.

The General Sherman is considered the largest single tree in the world by volume — according to the U.S. National Park service it is a whopping 1,487 cubic metres — and it is 31 metres in circumference at its base.  

Brigham detailed the efforts to protect the tree for As It Happens guest host Carole MacNeil. Here is part of their conversation.

Ms. Brigham, how close is the fire right now to the General Sherman?

There was a spot fire ... quite close to the General Sherman, less than a mile away.

And how is that being handled?

There is a large crew of fire personnel in Giant Forest right now watching out for all of the trees, including the General Sherman. And they were able to very quickly cut a line around the spot fire and put it out.

Christy Brigham is the chief of resources management and science, Sequoia & Kings Canyon National Parks. (Submitted by Christy Brigham)

Forestry workers have also wrapped the General Sherman in aluminum blankets. How does that work?

The purpose of that wrapping, It is a wrap called structure wrap. It is the same material that firefighters use in their emergency shelters. The goal of that wrap is [to] keep embers away from old fire scars on the General Sherman, places that could allow fire to get into the trunk.

So how much of the tree is covered?

Up to about 12 to 15 feet. It's taller than it looks in the photo because the tree is so big.

It is a feeling of eternity to stand next to the tree, you can really feel its age and size and its presence.- Christy Brigham, Sequoia National Park 

If fire does arrive, I mean, how does it protect the tree? Tell me a little bit more about fire scars.

Giant sequoias are incredibly well adapted to fire, they actually need fire for reproduction and to thin out the forest. They have bark that is 12 or more inches thick that protects the tree quite well. But a tree as old as Sherman has survived many previous fires, 80 to a hundred. And those fires have burned through the bark in some places. And in those areas, if an ember were to land and get going in there, it can light the middle of the tree on fire, which can eventually kill a big tree, even under low severity conditions.

So what we're hearing is that fire ... in the giant forest is low severity, two to three foot flame lengths. But we still wanted this extra layer of protection for the General Sherman.

The General Sherman has a circumference of 31 metres at the base. Firefighters here are attempting to protect the tree from the KNP Complex wildfire. (Sequoia and Kings Canyon National Parks)

You've also taken another layer of protection, that is removing the vegetation around it.

Yes. And that's done to keep the fire away from the trunk and also to prevent heat pulses to the roots of the tree that can injure the tree.

How old is the General Sherman?

We don't know. The estimates are anywhere from 2,100 to 2,700 years old.

What's it like to look at the General Sherman, to look at this tree?

It is an incredibly special experience. Every time I go up there, which I do regularly, I'm always chatting with the visitors about how they feel looking up into the branches of this tree and seeing its magnificent size. It is a feeling of eternity to stand next to the tree, you can really feel its age and size and its presence.

A feeling of eternity?

Yeah, I mean, how often do you stand next to something that's been alive since the Roman Empire? It really takes your mind into deep time.

Have you ever lost a sequoia to fire?

We have. We have lost in the Castle fire last year, all of the Sequoia managers...together, we lost between 7,500 and 10,600 sequoias. And we know that we lost several hundred in the park.

What's that like?

It's devastating. Many of us cried when we saw the impacts and to stand in groves that had devastating fire behaviour ... I personally feel like I failed the trees. They've survived so many previous fires, and climate change and fire suppression have really pushed them to the brink. And to see fires that are able to take these trees and kill them after they've survived so much is just heartbreaking.

Smoke drifts in the Giant Forest in the Four Guardsmen area of Sequoia National Park on Saturday. The giant sequoias are wrapped to protect them from the fire. (Sequoias and Kings Canyon National Park Service )

And yet here we are again, on the brink.

Oh, I know. It's terribly frustrating and it is so distressing to not have been able to do more, although I will say that Giant Forest is very well protected and all the prescribed burning we've done there... every indication is that the fire behaviour in that forest is very mild and those trees are doing great.

Other groves that we have not been able to treat with either thinning or fire, we are worried about and we may see some negative, some bad fire effects and some dead sequoias in those groves.

What about the community of Three Rivers overall? What's happening there?

The community is doing great. It is a fantastic town that really pulls together. People are cooking barbecue for the firefighters and dropping off signs and gifts and really appreciative of all the efforts of the huge number of fire crews and engines that are in town right now.

Community protection is the number one priority on this fire. And the community really appreciates that. Part of the town is under a mandatory evacuation and is evacuated and the rest of us are under a warning and have our belongings packed up and ready to go.

Would it be hard for you to leave, considering your attachment to the sequoias?

Yes, it would be.


Written by Andrea Bellemare. Interview with Christy Brigham produced by Niza Lyapa Nondo. This Q&A has been edited and condensed.


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