Has anyone any experience of dealing with this?

We have managed to work on a bank opposite the house that was full of it. It has taken 3 years but we are finally on top of the piece that we have tackled.
First of all we burned it with a parraffin flame gun, then we spot treated the crowns by spraying continuously with weed killer, agricultural strength & commercial 'Root Out'.

Anyone else any suggestions?

I think you are doing just about everything possible to cow it into submission. It's a horrible pest here where I live (our climate is quite similar to the UK's), and classified as a noxious weed.

About the only other thing I would attempt would be to try to smother it with plastic sheeting, but unless you can completely cover the area it probably won't work well.

Kingfisher

I'm surprised any has survived after that treatment! How much is left?

Last night I spotted a few weedy shoots coming up from the crowns which are about 18" in diameter & very woody so I was out again with the spray. I believe the runners can go 8m outwards & 10m down according to the Environment Agency site.
It can also come up through roads & concrete thus endangering foundations. It is illegal to spread it or dispose of it other than a licenced site. You must burn it in situ or pay for specailist removal.
It is a big problem on river banks as you cannot spray because of the wildlife in the water, but it seems it is a big problem countrywide.
I did hear of one recommended way avoiding spraying to get rid & that was to inject into the stem in the second section up but this must be back breaking & considering they have lots of stems that is a big task.
We are quite pleased with our progress but it is goping to take a lot longer.

I think you have to simply starve it out--every time you see it poke out a shoot, chop it back. Eventually it will die, as it needs chlorophyll to live. It's a slow process, though.

Kingfisher

I remember when on a trip in Cornwall they had a big problem with what I think was Japanese knot weed just off the coast. The locals said that it had arrived reasonably recently from shipping, and had completely taken over the near coast line. Because here it was such a large area problem I don't think there was much being done to try and stop it but I could be wrong.

This post was last modified: 22-04-2007 01:00 PM by riana.

Riana , there is a Cornwall Knotweed Forum to battle it in Cornwall, we came across it when doing research into the problem. Knotweed can make it very expensive to clear a site for building & it has to be done because of its tenacity.

We had JKW in our garden when we returned after an absence of 3 years. Weedkillers are a no-no as far as I'm concerned, so we set about eradicating it by uprooting every plant we could find and burning them, then each year we would destroy any shoot which appeared. While it has taken 5 or 6 years, we are now JKW free.

My husband wasn't keen on weedkillers also but as this was well established area of JKW of about 20 years, we needed a bit of extra help. The shoots that I sprayed were done with spray with wand nozzle that I used for spot treating thus lessening the impact on surrounding vegetation then as the crowns were hard I put weedkiller into little pools in the trunks of the plant so that it soaked into the crown. At first the bank was bald due to the flame gun  but I have since re-seeded it with a wild grass mixture & it is doing really well.
I don't think digging was an option for this location as we did not want to de-stabilise the bank so spot treating it had to be.
One thing that was funny to see was the Goldfinches, Robins  & other birds come down from the trees to eat the toasted insects. Talk about opportunity.

This post was last modified: 24-04-2007 10:27 AM by tibbar.

Would not have been funny if they ate the insects that had been effected by the weed killer

The burning took place well in advance of the weed killer I am not that reckless or stupid .

This post was last modified: 24-04-2007 03:35 PM by tibbar.

Has the bunring and weedkiller worked in the long term? Hope it has and that you've managed to get rid of it all!

The initial burning took place several times every timesome shoots grew & then we went to spot treating.. Now this is the 3rd summer & we are getting a few very spindlely shoots popping up so we are spot treating those. We did last year re-seed it with a rough grass & that has grown fine so we know that if the spot treating will kill some grass off but it will recover . It can take 5 years or more. We only started this as a safety measure as the knotweed was so high it was reducing visibility & affected safety of the kids & other cars, but it seems to be working.

Great to hear it is starting to work, it is a real struggle to almost completely get rid of the weed like you have over the past few years/

Wow! You seem to love your weedkillers. I had a little bit of Knot Weed just on the fringe of one of my woods. I kept an eye on it for three years but it wasn't able to get a hold. I think it was because of the stiff competition from the trees on ether side of it. Its gone know! If your looking for an easy and environmental friendly way to get rid of Knot Weed I would sagest planting trees in the infested area, Hazel would be perfect as its fast growing and gives good shade.

As a mater of interest has anyone tried Organic solutions to this problem?

This post was last modified: 18-11-2007 11:12 AM by treetops.