Using heat source to kill weeds

We are invaded by strong weeds from behind a metal fence that we cannot reach.

would an electric hot air weed burner similar to this:

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Would this be a useful kind of thing to fight a war of attrition or just a waste of time?

Reply to
john west
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£45 would buy a *long* supply of weedkiller
Reply to
Andy Burns

Waste of time - it burns the green top off the weeds and leaves the roots to grow new growth again.

Glyphosate will be taken in by the leaves and translocate to the roots and kill those off as well. It'll last longer before they become an anoyance again.

Reply to
Mark Allread

Hot air guns, flame guns, gas guns, whatever, work by killing the top growth of the weeds by rupturing the cells (it's not necessary to burn them to ash!). Some weeds will be killed right off, but deep rooted weeds will re-grow. You'd be much better off using something like Glyphosate, that works slowly and diffuses through the whole plant, roots and all, and kills it completely.

Do you know what the weeds are? If not, put some pictures on to an image-hosting site such as ImgBB

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with a link here and someone will identify them. For your sake I hope they're not Japanese knotweed.

Reply to
Chris Hogg

I agree. I have an old Sheen weed burner its noisy, smelly, looks impressive, but useless at long term weed eradication. Go buy some Glyphosate.

Mike

Reply to
Muddymike

Well if the length of the link is anything to go by, if nothing else it will collect a lot of metrics for google and others on who is looking at it.

Brian

Reply to
Brian Gaff

And not presumably scorch everything within reach either. I'm in two minds about this sort of thing. To be hot enough it should really burn the things and if you start a fire, you had best be able to stop it, especially if somebody elses property is involved. Brian

Reply to
Brian Gaff

Actually, no Brian, you don't need to burn them, just cook them. And glyphosate spray can be just as damaging if applied carelessly, for example on a windy day. Plants some distance away from the intended targets can be killed.

Reply to
Chris Hogg

Context is everything.

What sort of weed?

Is it invading a flower-bed where you don't want to risk the collateral damage that you will probably get with Glyphosphate (unless you use the gel).

Reply to
newshound

In message , Chris Hogg writes

Glyphosate will kill Japanese Knotweed but may need repeated applications.

I think the chemical was designed to kill Couch grass and is very effective on grasses. There are some weeds it doesn't touch but I can't find a list:-(

Dead Nettle?.....

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Reply to
Tim Lamb

It has problems with plants which have surfaces resistant to chemical penetration such as ivy, and to some extent holly, and horsetail - which has a surface covered with silica.

Reply to
Jeff Layman

Well they're dead already so there's no need! :-)

More seriously I find that a glyphosate + something else (longer term) weedkiller that I use on my gravel drive kills the grass almost immediately but 'broad leaved' weeds take quite a bit longer.

Reply to
Chris Green

Advice on how to, here

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There are a surprising number

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but I don't see dead nettle there. AIUI weeds that produce prolific amounts of seed are most likely to develop resistance, I presume on the basis that the more seeds there are, the greater the chance that amongst them will be some glyphosate-resistant ones.

Reply to
Chris Hogg

In message , Chris Hogg writes

I found lots of articles about acquired resistance but nothing about plants which ignore it. I suspect there are more about than Jeff's list but not ones that grow in my veg. patch.

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Reply to
Tim Lamb

In article , Brian Gaff writes

You're only supposed to singe them not burn them to a frazzle.

Reply to
bert

you are supposed to heat the soil to kill seeds

well beyond frazzle

Reply to
Tjoepstil

Absolutely not! That is not what flame guns are for or how they're supposed to be used. If you use one that way then you're doing it wrongly and wasting a lot of fuel with little benefit.

Reply to
Chris Hogg

As a kid I worked in a market garden where potting soil was sterilised by putting it at the top end of a long slightly inclined tumbler drum which had a king huge flame gun/blowlamp torch pointing from the bottom up the middle of the drum. As the soil tumbled down to the bottom of the drum it would be a) weed seeds killed b) fungal spores virus/bacteria killed c) dried.

A nice pile of dry sterile soil formed at the low end of the drum, ready for mixing with peat/sand to produce potting compost.

Nowadays I believe they achieve the sterilisation process with steam .

Reply to
Chris B

Oh, quite, I agree absolutely; a big Sheen-type flame gun would be very useful for sterilising bulk compost in the way you describe. But that's not what is being considered here, where the OP was asking about killing weeds in situ. The technique is to walk slowly over the weedy area, waving the gun to and fro to wilt and collapse the weeds, which subsequently die.

I had one. Great fun to use, if a little hairy to start. It always seemed to go through a 'flame thrower' stage, with gouts of burning paraffin shooting out about 20ft before it settled down. I gave it up in favour of glyphosate. A mate of mine also had one. He managed to set fire to his neighbour's hedge.

Reply to
Chris Hogg

I had a weed wand. It worked sort of. But then glyphosphate only kills existing weeds and breaks down on contact with soil. New seeds eventually arrive and grow. So either way repeat application is always necessary - filling leaking bucket syndrome.

Reply to
bert

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