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Comment by tsomctl | Hacker News Reader

Also, when these fires burn mature forests, they don't actually burn the huge trees, just the smaller brush. However, they are so hot that they kill the huge, mature trees. So a couple of years later, you have a huge amount of dead trees ready to burn again.

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This description is painting with a wide brush across many different western tree species.

A douglasfir forest that burns is going to behave much differently than a late-successional hemlock one.

Why is that? Sap content? I just started reading Hoadley's "Understanding Wood" [0], which has gotten me interested in wood's characteristics.

[0] https://www.amazon.com/gp/product/1561583588/ref=ppx_yo_dt_b...

Some species are specifically adapted to either be able to survive frequent brush fires, and some even require them for seedlings.

Douglas-fir trees have very thick, insulative bark that prevents the live tissue from dying as readily when there's fire. Sequoia trees have cones that are glued shut by resins that only melt after a hot-enough fire, so they can then land and germinate in burnt-over ground.

https://en.wikipedia.org/wiki/Serotiny

https://en.wikipedia.org/wiki/Pyrophyte

Thanks for explaining! Trees are amazing.

And to connect the dots, the smaller brush will return every year. So there's really no meaningful limit here; it can be this bad or worse every year to come.

Oh, I did not think nor knew about that one. I was more curious about does this have the same effect as controlled burning / prescribed burning but this seems to be making things even worse then. Thank you all for answers :)

Prescribed burning is usually done outside of the peak season (often in the later Autumn) just so it is more controllable and less intense.

It's amazing how fires can differ. Many "good" fires just essentially smolder for months, growing very slowly until the autumn precip douses them. The FS just lets them burn if they don't threaten any structures. I've even hiked directly over smoldering ground before, with no danger.

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