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Flame Weeding

 
Jason Tomblin
Posts: 31
Location: Fraser Valley, BC Canada
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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
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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.

FAST
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.

MOVING
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.

RESULTS
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.



 
Jordan Lowery
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Posts: 1528
Location: zone 7
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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.
 
Ivan Weiss
Posts: 171
Location: Vashon WA, near Seattle and Tacoma
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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."
 
R Scott
Posts: 3304
Location: Kansas Zone 6a
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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.
 
Taylor Stewart
Posts: 45
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Here's some info on flame weeding in veggie production:

http://www.agrisk.umn.edu/cache/ARL02969.htm

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
Posts: 31
Location: Fraser Valley, BC Canada
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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
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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
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Location: Lower Mainland British Columbia Canada Zone 8a/ Manchester Jamaica
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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
Posts: 100
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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
Posts: 132
Location: Missouri
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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.

Ray
 
Suzie Browning
Posts: 48
Location: Southwestern Ohio
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Can anyone tell me how flame weeding along a welded wire fence will affect the fence itself? Will it shorten the fence's lifespan?
 
Taylor Stewart
Posts: 45
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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.
 
Matt Grantham
Posts: 76
Location: Napa CA
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I know Curtis stone talked about this technique. if I recall he kept an area covered with a tarp then uncovered it water it lightly to get weeds to sprout and then used the torch. maybe its more effective with sprouting weeds?
 
Joseph Lofthouse
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One of my neighbors ended up in the hospital with severe burns because his flame-weeder flared up.

One of my collaborators uses a flame-weeder and says that she loves it. It's especially valuable for weeding tiny-slow germinating species in a vegetable garden (carrots). Because she can plant, and watch the row carefully, then run the flame-weeder over the row at the first sign that the crop is breaking the surface.

Around here in the desert, flame-weeding pretty much has to be confined to tilled fields. We burn-off last year's weeds in early spring, but the window of opportunity is narrow.

From a purely pragmatic standpoint... Flame weeding is like mowing the lawn, it's a chore... Drag out the equipment, get it operational, work with it long enough to feel like the set-up time is well spent. When I weed with a hoe, I can chop out one plant in passing. I can weed a single row, or for most of the day with little fatigue. Dragging a hoe around is easy. I can use it as a cane. The weight of my custom hoes is about 2 pounds. I can use those all day long. The typical flame-weeding setup weighs closer to 30 pounds. I do enough carrying of heavy things during the season without lugging around heavy tools.

For the cost of buying all the equipment necessary for flame weeding, I could buy about 8 hoes.

Flame weeding is only possible if I am part of The Corporation... My local blacksmith can make a hoe out of scraps, and a sapling.









 
Su Ba
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I recently added a weed flamer to my homestead farm equipment. Since I've only recently acquired it, it has not seen much use yet. I flamed the weeds and grass growing back along 2000' of fenceline. All the regrowth was short, less than one inch high, so it was young and small. The creeping grasses were just beginning to send out new growth and I flamed those tips. I mounted the propane tank (a 5 gallon tank) on a backpack, so I was able to walk quickly and flame as I went. Three days later I checked to see how things looked. Not bad. I'm happy with the results. But I see that I need to flame the tips of the kikuyu grass a bit longer.

The reason I bought the flamer was to eliminate using roundup along the fenceline. It's the only place I use roundup and needed to find an effective way to keep the grasses from growing up into the fence (the fencing rusts away here if the grass is allowed to cover it. I guess it has something to do with our vog.) I've tried a variety of other ideas but they didn't work out. Now I'm pleased to say that I've found a way to totally eliminate chemical herbacides from my farm. Hurrah! No more roundup forever!

Now I have almost 2 miles of fencing still to flame. I'm curious how much propane it will require. While I'm not thrilled about using propane, I feel it's a far better alternative than using roundup.

Joseph, I can't envision using the flamer to replace my hoe. No way! But I also can't see me hoeing 2 1/2 miles of fenceline -- both sides, once a month either. So I'll keep my hoe sharp and the propane tank full. 😄
 
Rick English
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Here is the one I bought a few years ago:
Red Dragon VT 2-23 C Weed Dragon 100,000-BTU Propane Vapor Torch Kit

I am tempted to offer to sell if for half price in its lightly used condition.

Either it is too wet where I live, or the weeds are too tough. It doesn't seem to do much more than waste time for me. I suppose there is a place for it, but I haven't figured one out for myself yet.
 
Roy Hinkley
Posts: 200
Location: S. Ontario Canada
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I have some spots where Periwinkle is taking over. Last fall I scorched a section and it looks like it's knocked it right back.
I'll be doing a much more extensive treatment this year.
 
Troy Rhodes
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I found it to be stinky and smoky and used up a lot of propane, and the grasses were back in 3-4 days, more vigorous than ever.

If you use it even close to any galvanized fence, the zinc burns right off and you get instant rust.
 
alex Keenan
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Does making a long burn pile in the garden each fall and spring count?
We have alot of dead fall and there is a constant fight with honeysuckle bush.
So I am always creating a pile of stuff that is too odd shaped to run into a chipper easily.
This get dragged on to a pile and burned. Burning tends to kill everything and leaves a layer of ash and charcoal.
So we move it from place to place each year.
 
Dale Hodgins
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I have watched a flame weeder at work but never used one myself. My cordless electric hedge cutter removes weeds much faster. They will pop up again, but they cut so fast that it's no big deal to cut them again in a month. I prefer cutting to pulling weeds out by the roots. With cutting, you get the same weakened plants coming up again. When they are pulled out by the roots, it creates the perfect environment for new weeds to start.
 
Su Ba
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Troy Rhodes wrote:
If you use it even close to any galvanized fence, the zinc burns right off and you get instant rust.


True! While I'm using the flamer along the fenceline I'm not actually doing the fence itself at all. My fenceline are already bare two foot on either side of the fence, so I'm targeting tropical tendrils and some new seedlings. I'm flaming those seedlings and tendrils tips as I walk by at a decent speed. Except for the kikuyu grass, the flamer knocked everything down. Looks like the kikuyu needs a tad more attention. My plan is to be able to walk at a speed so that I can flame the entire fenceline in two hours. I don't know if that is possible because I have some hills to climb while carrying the propane tank on my back. I'm still in the experimenting and learning stage. I don't even know if the propane will last for doing the whole fence. I haven't tried that yet.
 
Troy Rhodes
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grass seems to bounce right back, depending on the species I suppose. Some stuff it kills it outright.

Since I mostly had grass problems, I found it not very helpful...


Some of the tractor mounted rigs with multiple enclosed flames throw a tremendous amount of heat and it pretty much kills everything in the top half inch of soil and the ground is steaming after it passes. I'm sure that's more effective than my open flame. Has to take a lot of propane though...

 
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