Comment by Sn0wCoder

Comment by Sn0wCoder 9 days ago

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Prescribed burns do more than just burn up the dead wood to prevent forest fires. One of the other main goals is to kill invasive trees / plants while they are young. Doing burns in the fall after they have already spread their seeds for the next season would do nothing to prevent this. Another goal of spring burns is to stimulate the germination of specific tree species like the Giant Sequoia, Closed-cone coniferous, and some berry trees (maybe others). Most prescribed burns are done in early to late spring, not sure about summer burns.

If the only goal is to prevent forest fires, then in theory you could just send a hoard of people in to gather up all the dead wood at the end of each season, pile it up and have some nice fall bonfires, which might be fun. The main issue is the terrain harsh and would be very time-consuming.

seadan83 9 days ago

To your last paragraph - it's not just dead wood that is the issue - right?

In CA, there is a lot of shrubbery that turns brown and grasses.

Second, (west coast) forests that have not burned in a while look like a big brick of plant matter. Mostly living, dense, from ground to 30 feet high of plant matter that will combust when it is dry, windy, and a fire that is plenty hot to even burn the roots several feet deep.

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  • Sn0wCoder 9 days ago

    You are correct that there is typically more to wildfires than dead wood, as in they typically start with dry pine needles, leaves, tall dry grasses, and spread quickly via slightly taller vegetation up to the trees. There is a science to when a prescribed burn can happen, and there are seasons that will not be right for any given location, so the burn is a no go. The conditions need to be just right (wind so it does not cross a highway / blow into a farmer’s livestock, humidity, time since last rain fall. This has a lot to do with the rate at which the fuel will burn. Fuel less than 0.25 inches will burn within an hour of the last rain and may burn for an hour after igniting. 0.25 – 1 inch 10-hour, 1 - 3 inch 100-hour, 3 – 8 1,000 hour. So, the smaller stuff burns quickly but may or may not start a larger hour fuel. Once the larger fuel starts is when it becomes a serious problem since now it’s hotter and hotter and eventually starts the living trees on fire. If you were to manually remove the 100 – 1000 hour fuels, some of which are dead trees still standing or held up by living trees (unable to fall / stuck sideways). The risk of an all-out forest fire starting would go down, but still not be zero (like you say in a drought / super dry conditions). In the end you can only reduce the risk, never eliminate it (short of clear cutting).

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  • tekknik 8 days ago

    > big brick of plant matter

    as an avid outdoorsman, please explain this. I’ve never seen a “brick of plant matter”.

    I have seen overgrown shrubs and grass, but I’ve never seen the forest form a compressed brick of plant matter.

    Also if plants are living they have water in them.

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