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Flame Weeding

Jason Tomblin

Joined: Nov 17, 2011
Posts: 31
Location: Fraser Valley, BC Canada
I'm curious to hear people's take on using a propane torch as a method of weeding. The benefits and downsides I'd imagine are:

Possible Benefits
- Less soil disturbance than pulling
- Fast, Easy and Fun.
- Leaving the vegetation to crumble in place with goal being to boil the water in the leaves, not burn the plants.
- Ability to be selective, at least more so than a weed wacker or scythe.

Possible Downsides
- Cost and Dependence on Fuels. Unless one made their own gas.
- Heat damage to soil or insects?
- Risk of fire. It's suggested to have a hose and extinguisher nearby.
- Bylaw issues in urban setting

I haven't bought one yet, but they seem to make sense from my perspective as I struggled to make the list of downsides. I'd like to use it to control grasses and for selective weeding in my garden/row area. Would the flame weeding maintain the benefits chopping and dropping the weeds on the spot, as the leaves become brittle and disintegrate? Perennial grasses and tenaciously rooted plants would need repeated flaming to eliminate them, but this could be useful in the cause to cause disturbance and root shedding.
Ken Peavey

Joined: Dec 21, 2009
Posts: 2523
Location: FL
I've used a Red Dragon with a 20 pound tank and the tank dolly. I found it to be cumbersome and clumsy to the point that I concluded it was a terrible waste of time and money.
I was trying to knock down high weeds and grass on sloped rocky ground along the edge of a plowed field. Rocks cleared from the field had been tossed to the edge making it impossible to use a tractor or tiller-the rocks would easily break tines. The plow had left a raised ridge on the uphill side of the field. Even if I had not piled up the rocks, using a tiller would have been precarious due to the uneven ground. The project area was several feet around a field 600' x 100'. I was able to work about 100' before tossing in the towel.

The flame did the job of knocking down the weeds and did it quickly. The flame does not need to ignite or burn the weeds, it wilts them. Dry stems will *pop* as steam pressure explodes them open. Note that this is not a dangerous explosion. Wide areas can be laid down quickly and easily.

The hassle comes because of the short hose from the tank to the wand. A longer hose can be purchased, and may have made a difference. The short hose I was working with required frequent moving of the tank. A full tank, plus the dolly, plus the hose and torch weigh probably 50 pounds. The wheels of the dolly are small and not suitable for moving over rough, rocky ground covered with high weeds and grass. I had to pick up the entire rig to move it. I got rid of the dolly, replacing it with a hand truck (bigger wheels), strapping the tank with a bungee cord. This was no improvement. I got rid of the hand truck, picking up the tank by the handle to relocate it every 10 feet. Without the wheels, it was more stable on the slope while I worked. With the wheels I had to find a level spot, then heave it about to keep it from rolling/falling.

While the grass was laid down almost instantly, getting further into the area was made difficult now that the grass mat fell in the direction I was headed. Rather than wilt the grass I had to burn through it to get deeper into the area-not desirable due to the risk of starting a brush fire. The grass was laid down but still in one piece. There was no raking it up, leaving an unsightly mess. The roots were left intact allowing regrowth within a couple of weeks. For what I wanted to do, the Red Dragon torch was not the right tool.

A Scythe followed by spreading mulch would have done the job much better. For clearing weeds between a driveway and a metal building, the torch did a wonderful job-quick/easy/long lasting.

Seed the Mind, Harvest Ideas.
Jordan Lowery

Joined: Sep 26, 2009
Posts: 1528
Location: zone 7
we have one, i don't like it. it lowers the natural succession back to zero every time you burn. which in the long run encourages more weeds and more work.

The ultimate goal of farming is not the growing of crops, but the cultivation and perfection of human beings. - Masanobu Fukuoka
Ivan Weiss

Joined: Dec 19, 2009
Posts: 160
Location: Vashon WA, near Seattle and Tacoma
Ken Peavey wrote:The hassle comes because of the short hose from the tank to the wand. A longer hose can be purchased, and may have made a difference. The short hose I was working with required frequent moving of the tank. A full tank, plus the dolly, plus the hose and torch weigh probably 50 pounds. The wheels of the dolly are small and not suitable for moving over rough, rocky ground covered with high weeds and grass.

I carry my tank on a backpack frame built for it. Works for me. But as my ex used to say, "You have a strong back and a weak mind. I like that in a man."

Pastured pork and beef on Vashon Island, WA.
R Scott

Joined: Apr 13, 2012
Posts: 3048
Location: Kansas Zone 6a
It has its place, the ability to mimic wild fires in a micro scale is really handy.

Another benefit I see is the ability to burn the seeds if you did not catch the weeds in time. Very handy to deal with things like cockleburrs late in the season.

"You must be the change you want to see in the world." "First they ignore you, then they laugh at you, then they fight you, then you win." --Mahatma Gandhi
"Preach the Gospel always, and if necessary, use words." --Francis of Assisi. "Family farms work when the whole family works the farm." -- Adam Klaus
Taylor Stewart

Joined: Feb 15, 2012
Posts: 45
Here's some info on flame weeding in veggie production:


I've seen some 4 row tractor mounted flamers as well. I've heard they do a good job in grain production. In my mind, adding another system to a tractor just increases the chance that something will break. The fuel has to be managed as well, which is probably why many organic grain producers stick with mechanical weed control.

I've used a torch for weeding before, it worked fine...but I did accidentally set a fence on fire (no real damage).
Jason Tomblin

Joined: Nov 17, 2011
Posts: 31
Location: Fraser Valley, BC Canada
Great link. Lots of specific info on how it's used. I'm still curious to know if the minerals and such would be intact in the weeds. I'd figure so but am not sure if anything beneficial in the burned plants would be vapourized.
John Polk

Joined: Feb 20, 2011
Posts: 6884
Location: Currently in Seattle. Probably moving 1 hour north by end of the year.
I wouldn't think so. Hot lava comes out of a volcano in a liquid rock form, and doesn't seem to be lacking any minerals.

Some of the other nutrients might be lost. Certain organic matter is commonly burned to concentrate the nutrients.
For example, banana peels and stalks are commonly burned. Their ash contains 40-50% potash (citrus rind ash contains about 27% potash).

Saybian Morgan

Joined: Apr 22, 2011
Posts: 582
Location: Lower Mainland British Columbia Canada Zone 8a/ Manchester Jamaica
I spent about 3 hours flaming weeding today, I can't even call it that. I too have ended up simply lugging the tank as nothing works in real country, it's designed for driveway maintenance. Every once in awhile the wind throws the heat or some smoke back at you, you whirl around and before you realize it the torch is either pointing at the propane tank or worse the hose. I had solarized moss and creeping buttercup with black plastic for 7 months hoping to place it once everything was truly dead due to lack of light. It took all summer and all winter but I checked today and there were only a few white stalks left searching for light. Bingo I thought if this week loves waterlogged acid conditions, the plastic should keep it dry and if I burned the moss I might have enough ash to change the ph and keep slugs away long enough for some grains to sprout. It was such a pain in the ass, I was boxed in with green so I was hoping to start a fire and just watch, buttercups do not burn they don't care about me at all. They sit there with the flame on max just dancing eventually they turn purple and wilt but there will be thicker stronger shoots in 3 days or less, the moss started to brown and of course it began to rain. After that I was just wasting propane, the line between fires, quick wilt, and no effect but standing there torching 6 square inches for 30 seconds is really thin.

I don't doubt this torch works on some things but I havn't found them yet, anything it works on is most likely going to burn down the forest, everything else is a plant I'd highly recommend for stopping fire. It's true use is weeding asphalt cracks and hardscapes, I couldn't get that ground to warm up at all, there where slugs out and about on spots I tried to burn 10 minutes ago and they showed no signs of being there when I was pseudo burning. I had fun for the first half hour, then the tank get's on your nerves cause it's a hazard and it get's hot if your not using it in the rain.

FYI if you buy one, don't even touch the tip after use, even way after use, just lay it against some really water filled plant that wont burn or light up the country side, and even when it's done making the siering sound don't bother touching it. Let's just say I've learned multiple times, it usually touches my leg when im putting it away. I think the reason it does such a good job on hard-scape surfaces is because the surrounding brick or tar get's hot and transmits the cook to the base of the plant.
Rich Pasto

Joined: Dec 13, 2011
Posts: 100
know when to use it. It's a tool just like anything else. Use it when the plant is 7-10 days old, before the roots can store energy, or use it on a very hot, late summer day. Plants are already struggling, and hitting them with a flame does them in. As mentioned above, it can and will also toast many of the ungerminated seeds on or near the surface. If you some dandelions, toasting the seed head is really effective.

Half of my backyard was over run by weeds last year. I torched them in august. compared to last year, I have have 99% less weeds, and they are strangly little things trying desperately to grow. Since I didnt disturb the soil, none of the other million seeds have germinated. So far it has worked so well, I doubt I'll need to use it again this year. Your only other option without using chemicals is to pull weeds or whatever by hand. Just as effective, just takes longer.
Ray Cover

Joined: Apr 11, 2012
Posts: 132
Location: Missouri
This may be a no no I'm not sure, but if your talking about small areas like mulched paths I use a tarp.

I mulched my blackberry bushes to control the weeds around them last year. this year I had a few patches where grass is trying to peak through the mulch. I folded up a tarp, placed it over the weeds, and laid a couple boards on top to hold it fast to the ground. in about 2-2 1/2 weeks that grass will be killed back. Smothering it from light works on small selective areas. Not the way I would want to try and control a large area but for small areas that are mulched for the purpose of weed control anyway this works well for me.

Suzie Browning

Joined: Jun 10, 2010
Posts: 48
Location: Southwestern Ohio
Can anyone tell me how flame weeding along a welded wire fence will affect the fence itself? Will it shorten the fence's lifespan?

On the border of Zones 5 & 6 on the last 2 acres of what was once a large farm.  Flat, flat and more flat!
Taylor Stewart

Joined: Feb 15, 2012
Posts: 45
If the wire is heated too much any coating will burn. If it's galvanized the zinc is pretty noxious when heated and can make you pretty sick if you breathe in too much of it. When the coating is gone the steel will rust shortening the lifespan. The steel will also become brittle if heated too much. If you can direct the flame away from the wire you should be fine.
subject: Flame Weeding