I've had pretty disappointing results with flame-weeding.
I live in a rural area in the Western US with some acreage, and try to avoid the use of herbicides as much as possible when I'm controlling weeds and invasives on our property.
Flame weeding is far and away the most fun and satisfying way to deal with weeds, but it doesn't seem to do much for me beyond perhaps briefly annoying them.
I've tried both near complete obliteration, and damaging the weed somewhat lightly under the theory that it'll expend its energy trying to "repair" itself, and die out more effectively in the long term.
Neither seems to work well with the thistles and other plants I'm fighting. I've even seen some thistles come back particularly strong after a fire. My theory is that seeds from competing plants are burned, but thistles underground network of rhizomes are unaffected, and take advantage of the lack of competition.
I recognize that fire is a natural and important part of the landscape and ecology of the West, but when it comes to crisping weeds, it seems to have limited use in my experience.
There are adaptations against that, giving even greater tenacity and resilience. There are a whole bunch of plants that rhizomes. Attempting to pull out the root structure, in practice, helps propogate them via root division. Examples of such plants are running bamboo, kadzu, feverfew, bermuda grass, etc.
For these kinds of plants, it’s better to change soil condition: use a technique called “sheet mulching”; it delays things enough to establish a different soil condition and different plants. Even then, it may not work.
Fire is a great way to help restore soil. Some plants, as you found, come back stronger.
The best way I have found to get rid of weeds without herbicide is to make sure something else is growing on there.
Some weeds are pioneer plants. They come in on disturbed, and desolate soil. As they grow and thrive, they change the soil conditions so that other plants can grow there.
These plants are tenacious, but ironically, changes things so that they are out-competed by other plants. If you fight them, they dig in and get stronger. If you help them fulfill their ecological function, then they help make way for something else.
I keep trying to explain this to my father, who insists that mowing his entire noxious-weed-covered property is the only way to deal with them. Unfortunately, that's the only sure-fire way to keep them sticking around - scalp the soil bare 5x a year.
Fellow West Coast flame weeder here! Our weeds are especially tenacious, for the reasons you've described and for our boom/bust water cycles.
They tend to store enough excess carbohydrates in their roots to re-sprout three or four times. While this can make them seem utterly invincible, they will in fact deplete their resources if you stick with it long enough. I usually plan two or three flame weeds during spring, followed by some later touch ups if fire season allows. (Always wet the ground beforehand if it's dry out).
This also works with weed whacking. Himalayan blackberries, for instance, seem to only be able to resprout two times. So I knock them down as low as possible with a hedge trimmer, then touch up the new growth with the string trimmer about six weeks later, then again six weeks after that.
Thistles are usually a poor-soil indicator. Let them grow. They bring up nutrients from deeper underground. Then mow 'em down to mulch and you're improving the soil.
I have seen better versions. The incoming air should be preheated with the exhaust. The exhaust should be barely warm. The weed can be part of the fuel. OH, and of course in the future it will be solar powered and run on the blockchain!
Interesting to hear that this is used for organic crops, in lieu of chemical pesticides. I wonder if people who eat organic food would be less likely to do so if they knew that fields were being flame-throwed multiple times a season in order to avoid using pesticides.
It's a complex question, since it involves personal safety, environmental harm, and fossil fuel combustion.
There is a lot of organic farming that is worse for the environment than standard herbicides. But you can't tell people that without massive downvotes and screams of 'but the chemicals'
E.g. flame weeding, seriously?
Not getting it.. also curious about some more examples with references about the organic but ecological worse than herbicides sins please.
Otherwise, typical like a lot of this type of fuzzy organic-blame comments on everything like that, because those people must be crazy and get it wrong vibes.. but won't say much more concrete because of the massive downvotes, you know??
Plowing to remove weeds, which you pretty much have to do is bad for the soil and uses a lot more fuel than spraying a little bit of chemical.
Crops that yield better mean much less land is used. Thus fertilizer is generally better than none, though this is complex. (Crop rotation is still good)
> I wonder if people who eat organic food would be less likely to do so if they knew that fields were being flame-throwed multiple times a season in order to avoid using pesticides.
It's much better for the soil and crop than cultivating multiple times a season, MUCH less expensive than hand pulling, and is potentially better for the environment than using herbicides.
I’m not sure I follow. What about using fire would upset organic vegetable consumers? The fact that a little bit of propane is burned in the process? Plenty of diesel and gasoline is burned by tractors and machinery on any farm, organic included. Adding a little propane to the mix seems like a good trade of to me, if the result is less chemical herbicide.
I've experimented with this and other methods for home use. One thing I've found very effective is steam and boiling water - especially for pavers. It does more than just killing the leaves - the boiling water penetrates and kills roots.
What's the process for steaming a patch of soil? It seems like running a mobile autoclave would be really good at killing everything in the soil, which is probably both good (gets rid of the weeds) and bad (kills everything).
Are there mobile soil steaming systems? Certainly that'd be way less toxic than dumping a bunch of chemicals all over.
I used a Kurtcher (I think?) steam cleaner that is used to power a steam mop, but just had the spray thing that I think it for cleaning windows.
I'm not aware of any special devices, but I did think that for paving specifically there would be a market. We had a kid who was crawling and didn't want to use toxic poisons on the paving, so I had to think about alternatives.
But I could imagine, it doesn't only kill the roots, but all microorganisms around them as well so you'll end up with dead dirt instead of a proper soil.
I also wonder about the energy footprint for heating that much water... My intuition screams "far too much to be a reasonable scalable alternative".
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[ 3.1 ms ] story [ 81.9 ms ] threadOy...
> British thermal unit (the amount of heat needed to raise one pound of water by one degree Fahrenheit, equal to 1.055 x 103 joules)
I live in a rural area in the Western US with some acreage, and try to avoid the use of herbicides as much as possible when I'm controlling weeds and invasives on our property.
Flame weeding is far and away the most fun and satisfying way to deal with weeds, but it doesn't seem to do much for me beyond perhaps briefly annoying them.
I've tried both near complete obliteration, and damaging the weed somewhat lightly under the theory that it'll expend its energy trying to "repair" itself, and die out more effectively in the long term.
Neither seems to work well with the thistles and other plants I'm fighting. I've even seen some thistles come back particularly strong after a fire. My theory is that seeds from competing plants are burned, but thistles underground network of rhizomes are unaffected, and take advantage of the lack of competition.
I recognize that fire is a natural and important part of the landscape and ecology of the West, but when it comes to crisping weeds, it seems to have limited use in my experience.
For these kinds of plants, it’s better to change soil condition: use a technique called “sheet mulching”; it delays things enough to establish a different soil condition and different plants. Even then, it may not work.
You need some method to destroy the roots.
The best way I have found to get rid of weeds without herbicide is to make sure something else is growing on there.
Some weeds are pioneer plants. They come in on disturbed, and desolate soil. As they grow and thrive, they change the soil conditions so that other plants can grow there.
These plants are tenacious, but ironically, changes things so that they are out-competed by other plants. If you fight them, they dig in and get stronger. If you help them fulfill their ecological function, then they help make way for something else.
They tend to store enough excess carbohydrates in their roots to re-sprout three or four times. While this can make them seem utterly invincible, they will in fact deplete their resources if you stick with it long enough. I usually plan two or three flame weeds during spring, followed by some later touch ups if fire season allows. (Always wet the ground beforehand if it's dry out).
This also works with weed whacking. Himalayan blackberries, for instance, seem to only be able to resprout two times. So I knock them down as low as possible with a hedge trimmer, then touch up the new growth with the string trimmer about six weeks later, then again six weeks after that.
It's a complex question, since it involves personal safety, environmental harm, and fossil fuel combustion.
The other funny thing on organic farming and chemicals is nicotinoids can be used. They break down, but before that happens, they're not great.
see https://www.ecfr.gov/current/title-7/subtitle-B/chapter-I/su...
Otherwise, typical like a lot of this type of fuzzy organic-blame comments on everything like that, because those people must be crazy and get it wrong vibes.. but won't say much more concrete because of the massive downvotes, you know??
Crops that yield better mean much less land is used. Thus fertilizer is generally better than none, though this is complex. (Crop rotation is still good)
It's much better for the soil and crop than cultivating multiple times a season, MUCH less expensive than hand pulling, and is potentially better for the environment than using herbicides.
Are there mobile soil steaming systems? Certainly that'd be way less toxic than dumping a bunch of chemicals all over.
I'm not aware of any special devices, but I did think that for paving specifically there would be a market. We had a kid who was crawling and didn't want to use toxic poisons on the paving, so I had to think about alternatives.
https://www.kaercher.com/us/home-garden/steam-cleaners.html
I also wonder about the energy footprint for heating that much water... My intuition screams "far too much to be a reasonable scalable alternative".
I think the steamer is at least partially a flash boiler, so energy use isn't high. It isn't huge amounts of water it needs to boil.
https://www.youtube.com/watch?v=AP0yiOI8Qas