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Giant Sequoias and the 2020 fire season

Posted: Sat Sep 12, 2020 8:46 am
by milkfish
While I'm quietly freaking out over here from the east coast, does anyone happen to know if any/how many Sequoia groves are being impacted by the SQF complex? I know the Sequoias thrive on fire but are these fires so large it's killing the trees?

Re: Giant Sequoias and the 2020 fire season

Posted: Sat Sep 12, 2020 11:03 am
by freestone
milkfish wrote:
Sat Sep 12, 2020 8:46 am
While I'm quietly freaking out over here from the east coast, does anyone happen to know if any/how many Sequoia groves are being impacted by the SQF complex? I know the Sequoias thrive on fire but are these fires so large it's killing the trees?

This Inciweb report should answer your question. The Freeman Grove is the only grove mentioned that is directly threatened and resources are being allocated to minimize fire damage to it.

Re: Giant Sequoias and the 2020 fire season

Posted: Sun Sep 13, 2020 12:19 pm
by dave54
The giant Sequoia groves are considered high value resources and special measures are set up to protect them.
The large old growth are somewhat fire resistant. The smaller younger trees are fire susceptible like all young trees.
Giant Sequoia are serotinous. Heat from a fire is needed to open the cones and release the seeds. Their cousins, the Coast Redwood, are not serotinous.

https://www.fs.fed.us/database/feis/pla ... g/all.html

https://www.srs.fs.usda.gov/pubs/misc/a ... anteum.htm

Re: Giant Sequoias and the 2020 fire season

Posted: Sun Sep 13, 2020 2:25 pm
by tie
They are not burning, but they will all die in the next 50-100 years if we don't do something. The average temperature in California is expected to increase by 4.7 to 10.5F by the end of this century, and it could be much worse if carbon emissions continue to rise. The trees are dying from drought stress and beetle infestations [1].

It's sad when you see the huge redwood stumps from logging. What could those people have been thinking? Cutting down these magnificent trees for roof shingles?! They weren't thinking, I guess. We are doing much worse now, killing them all for the sake of our SUVs.

[1] https://www.theguardian.com/environment ... -years-aoe

Re: Giant Sequoias and the 2020 fire season

Posted: Tue Sep 15, 2020 6:12 pm
by dave54
tie wrote:
Sun Sep 13, 2020 2:25 pm
They are not burning, but they will all die in the next 50-100 years if we don't do something. The average temperature in California is expected to increase by 4.7 to 10.5F by the end of this century, and it could be much worse if carbon emissions continue to rise. The trees are dying from drought stress and beetle infestations [1].

It's sad when you see the huge redwood stumps from logging. What could those people have been thinking? Cutting down these magnificent trees for roof shingles?! They weren't thinking, I guess. We are doing much worse now, killing them all for the sake of our SUVs.

[1] https://www.theguardian.com/environment ... -years-aoe
You are mixing the two species.

The OP was about Giant Sequoias. You referred to the Redwood. Different genus, different climate zone, different soils, different wood properties.
The Giant Sequoia will be able to withstand climate change better than the Coast Redwood. The Redwoods are picky and survive in a relatively narrow band along the coast where conditions are right. The GS is able to withstand a broader range of conditions and has been planted around the world. There is some experimentation now to see if GS can be grown as a commercial species in plantations.

Re: Giant Sequoias and the 2020 fire season

Posted: Tue Sep 15, 2020 9:56 pm
by mort
dave54 wrote:
Tue Sep 15, 2020 6:12 pm
You are mixing the two species.
You could have read the article:
..."And now what I’m telling you is that the combination of drought, fire and insects is killing giant sequoias.”
-mort

Re: Giant Sequoias and the 2020 fire season

Posted: Wed Sep 16, 2020 5:01 am
by milkfish
I imported a map of GS groves into caltopo and laid over the fire data - for those interested. Looks like the Castle fire is affecting a few groves in the GSNM. For those interested: https://caltopo.com/m/40G9

Re: Giant Sequoias and the 2020 fire season

Posted: Wed Sep 16, 2020 9:48 am
by gdurkee
The semi-good news for fire and Giant Sequoia groves is they'll probably do fine. As pointed out above, they'll receive extra protection though, where there's been extensive prescribed burns previously, as in Sequoia Kings and Yosemite, that's probably unnecessary. Although the Creek and other fires are incredibly intense and well outside the norms for any Sierra fire this century, Giant Sequoias have, historically (3,000 years) had such fires go through groves.

A recent study looked at the size of fires in two Sequoia Groves over 3,000 years. Fire intervals were between 2 to 15 years and were from 150 acres to 900 acres. Significantly, the periods of shorter intervals and larger fires occurred during warm and dry periods.

The study said:
Sequoias can sustain very high fire frequencies, and historically they have done so during warm, dry times. We suggest that preparation
of sequoia groves for anticipated warming may call for increasing the rate of prescribed burning in most parts of the Giant Forest.
That said, there's a number of groves -- the majority -- that haven't had prescribed or wild fire move through them and do have huge amounts of fuel (deadfall and dense forest) that otherwise wouldn't be there were fire a normal part of the forest ecology. There could be some mortality even among the older trees (> 500 years).

As for drought, the study above pointed out GS survived the Medieval Warm. Two droughts of over 1,000 years from about 900 -- off and on -- to 1100. These droughts were enough to have completely dried up Tenaya Lake and other Sierra streams and lakes. So, again, there's hope based on historical data.

The bug killed tree case cited in the article seems to make a generalization of a single tree to all Sequoias. Nate Stephenson, quoted, does say it's worrisome and no question he's the expert on GS. Without more evidence, as he says, I'd not panic just yet. Also, it's arguable that because of the unnatural density of all the other species of surrounding trees (white fir and other conifers) that wouldn't otherwise be there were fire a part of the regime, the ground water is being sucked out at a much greater rate than otherwise, weakening even GS and making them susceptible to bugs.

Re: Giant Sequoias and the 2020 fire season

Posted: Wed Sep 16, 2020 8:49 pm
by dave54
mort wrote:
Tue Sep 15, 2020 9:56 pm
dave54 wrote:
Tue Sep 15, 2020 6:12 pm
You are mixing the two species.
You could have read the article:
..."And now what I’m telling you is that the combination of drought, fire and insects is killing giant sequoias.”
-mort
Hmmmm ..... A slanted opinion piece in a partisan yellow tabloid versus peer reviewed and published scientific research.

Which one to believe? That is a tough call.

Re: Giant Sequoias and the 2020 fire season

Posted: Wed Sep 23, 2020 8:31 am
by Wandering Daisy
"Who's SUV caused that?" Another way to look at it is: if that severe of a drought is part of natural cycles, just imagine how much worse it will be when the next natural cycle adds human caused carbon. And can the added carbon we cause become so high that the natural climate cycle cannot recover?