Japanese Knotweed

Davesnave

halfone wrote: »

Can you not also kill them by simply widdling on them?

I'd say that would depend on the size of the leyland cypress and the number of widdles, but a hedge of them would surely tax the most incontinent individual.

My point was that they are quite easily killed-off and straightforward to control, so not at all like JK.

A more appropriate partner to JK would be impatiens glandulifera.
https://en.wikipedia.org/wiki/Impatiens_glandulifera

moneyistooshorttomention

Himalayan balsam - not in the same category I feel as a destructive plant like Japanese Knotweed (anywhere) or leylandii (in the wrong location).

Yep...I've dealt with that too - organically. It astonished me just how easy it is to just pull it up (even for a pretty physically weak woman like myself = no problem). Followed by breaking the stem part way up and then putting the pulled-up plant somewhere it cant "start over" by regrowing. It was dead easy and darn quick to just walk through it going "pull/break/dispose and pull/break/dispose" again.

That plant wouldnt worry me either - I've yet to see a large enough "crop" of it that my heart would falter at the thought of a good pulling session or two dealing with it.

Davesnave

moneyistooshorttomention wrote: »

Himalayan balsam - not in the same category I feel as a destructive plant like Japanese Knotweed (anywhere) or leylandii (in the wrong location).

You are putting a human spin on this, rather than looking at the whole picture of the plant as an invasive alien species. I suppose relatively few gardens are seriously troubled by Himalayan balsam, but as something which damages environments, it's impact is much greater than most other aliens.

Yes it's easy to pull up when shorter than a person, but it doesn't stay that way long and its ability to travel and grow very fast means that there are never enough human volunteers to cope with it organically.....which is why there's so much about.

A friend of mine owns several acres of the stuff, if you string it all together. That's not a Sunday afternoon weed pulling session! It's obliterated most of the native riverside vegetation, which cannot compete. Because of its relatively weak root system, when winter floods come, the river scours out the affected areas taking fences and small trees with it and often changing its course too. It's seriously large scale habitat destruction, but because few people see it, no one bothers much.

Actually that 's not entirely true. My friend recently obtained a grant to improve his riverside and the balsam was part of the action plan, dealt with not by volunteers, but by chemical intervention, because it's quick and a darn sight more reliable.

When it comes to trees, in a human annoyance sense, then hybrid poplars and willows are the way to go.....Much harder to kill off than our friend the leyland cypress.

moneyistooshorttomention

Yep...riversides is where I've seen it - and been told all about how it gets spread around down the river by the other volunteers whilst we were busily pulling/breaking/disposing. The volunteers I was with wouldnt do treating with chemicals either for anything that can be dealt with in other ways - and hence I felt pretty well-informed about it by the time we'd finished pulling it all out. I was informed in great detail about just how many other species of plant were being affected by it/effect on riverbanks/etc.

I'm definitely not in the "leave it to it - because its Nature innit" school of thought and have got rather exasperated before now with "head in clouds" "Lets just leave Japanese Knotweed because its Nature innit and its edible" school of thought.

Though - back to JK - the usual reason for irresponsibly ignoring JK seems to be that the land-owner is too lazy to deal with it and I've certainly been astonished at seeing just how many conventional easily removable weeds there are around in some peoples front gardens.

Riggyman

D00gie72 wrote: »

OP is talking about JK in their neighbours garden. I know they may be absent but are you all really recommending they trespass to spray weed killer on someone else's garden?? I can understand getting an expert to confirm if it definitely is JK - but surely then its the owners responsibility to remove - the OP can't go in and get rid of it themselves surely?

If the knotweed in a neighbours garden was threatening to invade my garden, then yes I would spray it. Indeed I do. What are they going to sue you for? What loss have the incurred? Yes it's their responsibility, but do you feel lucky?

Riggyman

nobodyspecial wrote: »

If you are happy tresspassing on someone else's land, and committing criminal damage, by all means follow the advice above. Some people advocating that you do are the very ones that wouldn't want these chemicals sprayed haphazardly on their land, and would be screaming if it was done to them. By all means contact the owner and state your fears, but they may well want it dealt with by a professional. Also it's not illegal to have this on your own land, the op states it's not in their garden.

What criminal damage?

dc197

daveyjp wrote: »

Another post demonstrating a complete lack of knowledge about this particular species of plant.

You can't spray after flowering as it flowers right at the end of its growing season. Spraying will have very little effect once it has flowered as that season's growth dies off immediately aftwerwards.

Spraying in late July, mid August and early September is the usual approach. It flowers in mid to late September into early October then dies off above ground.

The point to be made was that one should not spray during flowering if the manufacturer's label says not to.
The post I was referring to advised to wait until flowering, then spray. Perhaps you should be remonstrating with them, not me?

dc197

alistairstubbs wrote: »

Glyphosate is a herbicide not a pesticide.

A herbicide is a pesticide.

Cite: http://www.panna.org/pesticides-big-picture/pesticides-101

deFoix

Boler1985 wrote: »

Sound Advice: Wait until the plant flowers then spray with glyphosate herbicide (e.g. Roundup) on the top and under the leaves. it will die. Next season if any regrowth spray again.

90% of the battle with JK is knowing its there in the first place!

I'll repeat myself again. Oh and btw I just red my Roundup label which says "For best results apply when the plant is flowering (usually August/September)...".

dc197

My posts all said not to apply while flowering if the label said not to.
Thanks for confirming the manufacturer's recommendation.