Undisclosed japanese knotweed on property

moneyistooshorttomention

Devon and Cornwall County Council do seem to have by far the best attitude to it from what I've ever come across - ie viewing it with appropriate seriousness.

I've read their info. about this with interest and that does seem to be a bit of info. that's missing from it though.

My suspicion would be that that info. is missing because no-one thought to put it in though - rather than because they believe "Once treated = it's total past history and continue as normal".

Logic tells me that if there are two levels of dealing with it:

- the chemical (3 years or so) treatment programme at one cost

and

- the total eradication of every last little trace of it/dig the lot out completely at a much higher cost


that the higher cost/more effort method of dealing with it wouldn't exist if the first method (ie chemical treatment) worked - ie restored the land to totally normal status/do as you please to it.

Hence I'm inclined to believe this person.

I'll keep my fingers crossed I come across the Pembrokeshire County Council official responsible for dealing with it out clearing it again (via the chemical method). I'll probably meet him or someone like him again in my travels - and will ask them too. But the one I've been talking to is certainly very knowledgeable about it - so if they (and a couple of local organic farmers that used to have it) say it's a "zombie plant" and the only way to "get back to normal" is absolute total removal of every last bit of soil that might contain it - then I'm inclined to believe them.

DaftyDuck

Davesnave wrote: »

At the very least, this person would need proper scientific evidence to support their interpretation of the situation......

I have never read this 'undead' info anywhere, but that's not to say it isn't true either. I'm just somewhat sceptical that it's correct.

Even double digging only goes about 40cm below the surface. Just saying....

Well, I am a scientist :rotfl:, so I'll wade in... even if it's just adding more addled info. But, I do also have first-hand experience of treating Japanese Knotweed! I did spent five years researching the side-effects of herbicides and pesticides on human nervous and respiratory systems.... mostly theoretical, so seldom a spade or spraygun in sight!

There's certainly no such thing as Zombie knotweed. Never will be. Never was, not even in an X-File or a John Wyndham novel! Like many plants, it can enter dormancy, and the rhizome can survive underground for a couple of years without light, before regrowth. But, it's far from unusual in that respect. Unfortunately, one of the triggers for inducing dormancy is being hit by under-strength or over-strength weedkillers.

There are claims that this dormancy can last 20 years... but I've only seen commercial sites claiming that timeline (as a fear-tactic against a competitor's methods). Maybe it can last that long but, if so, regrowth would be slow, weak and easily dealt with by further (correct) spraying.

Japanese Knotweed is NOT the devil incarnate, it's not the most prolific weed, and it is (honestly) fairly easily dealt with in most circumstances by an amateur, using off-the-shelf equipment and chemicals. Honestly. That's with both my keen-amateur-gardener floppy hat on, and my Large-Pharma-Goggles-and-mask.

Inciting needless panic and worry here on this forum by (mainly one) regular poster(s) is getting utterly ridiculous, and more silly by the posting. There is good information out there, information based on experience, science and sense, but it is being swamped by the "panic brigade" and Daily Mail lynch-mob (cue sadface photo of householder 'life ruined by Knotweed').

Knotweed was (and still is) grown for decades in large stately homes and passably grand farmhouses for a hundred years as a fine ornamental shrub, and hairy gnarled old gardeners kept it in check with nothing more than a fork and a bonfire. Still do, for certain. You don't see any of those grand houses tumbling down as ruins from the invading roots, or Capability Brown parks falling desolate.

Yes, in certain rare cases it has caused structural damage, but normally to pretty weak structures where it has been given free rein. Yes, mortgage companies are loathe to lend on properties 'blighted' by the stuff, but much of that is the "Panic Brigade" reaction catching on in the public, so resale value (all the mortgage co really care about) might be damaged.

Yes, it does need more control than it's currently getting, and there needs to be a better understanding of landowners' responsibilities - mainly the various councils, if I'm honest. Round here, our council did a very good job of spreading it whilst using a culvert cleaner with a rotary blade.... hmmmm.

Soil removal is certainly a possible way of dealing with Knotweed... except, where do you dump the soil? How deep? What happens to the bits that get blown off the lorry? Who pays? HOW MUCH???? What other environmental impacts does this scrape-and-bury technique have? And, and, WHY??? What possible benefit (aside from lining someone's pockets) can there be? Are you sure they remove every last rhizome... If not, do you dig away another ten lorry-loads, or use a small hand-held spraygun with about 12p's worth of herbicide?

Look, wild speculation by the ill-informed and neurotic is not the way to deal with this as a problem. An educated response based on facts might just help reduce the impact Knotweed has on the landscape and - more importantly - the impact it has on human psyche. Basing - and spreading - panic based on what some equally ill-informed character might say is - to say the least - ridiculous. Equally, I know the bloke in charge of environmental matters for this council under whose remit Knotweed falls. I wouldn't trust his knowledge on most scientific matters, and would certainly question his attitude to many wildlife issues. Part of that is money driven - Councils can't afford to employ folk who have any worthwhile qualification for dealing with these issues. However, at least council officials try their best to get and give accurate knowledge.

Of course, many organic farmers know their stuff and act appropriately Many do not. As an indication, from some 20 years plus ago, my lab had some flour beetles for experimental purposes. We ran out of the (scientifically produced and managed) flour in which they were reared. A colleague had the brainwave of visiting the (highly-regarded) organic food shop neat the lab and getting some of their finest flour. The beetles all died in a couple of days. We analysed the flour. Not only did it have higher-levels of pesticide than were (even then) allowed under EU regulatons, it also contained cyanide, lead and human faecal matter!

So, if anyone bothers to read all this tripe I've typed, take-home messages are:

No "Zombie" knotweed... I mean , seriously? :rotfl::rotfl::rotfl:
Dormancy for a couple of years - possibly a bit longer... but only if you treat it wrong
JK very easy to eradicate using chemicals, takes a couple of years, 3 to be sure.
Don't Panic, Don't Panic.... It's the panic that costs lives - and sanity!
Don't believe what "some bloke down the pub" tells you, as it's likely bilge!
Don't read and believe what the ill-informed post on the internet (including me!!!) without engaging brain first.

Oh, and don't read the Daily Mail. Just don't!:D

Davesnave

I think dig and remove is possibly the solution most favoured when waiting would hold up a construction project, with obvious financial consequences.

That's the only scenario, besides profiteering, in which I can imagine it being used instead of cheaper chemical treatment.

There are some specific environments where other methods are advocated, e.g. riverbanks, but I don't think it's helpful to complicate things further(!)

Oh, and the only stand of the stuff known to me here, is in the grounds of a "big house."

Freecall

DaftyDuck wrote: »

No "Zombie" knotweed... I mean , seriously?

Brilliant response!

As they say - Be afraid, be very afraid......

DaftyDuck

Oh, don't get me wrong, Dave: dig & bury is certainly a weapon that's useful and, in the case of large construction (say a motorway), it's effectively "free", as the spoil can be deep-buried elsewhere where infill is needed.

It's this "Garden will never be 'normal' again - sue everybody or kill the previous owner "carp that bothers me! Spreading panic and discord rather than a bit of rational fact and calm. Knotweed is easily and permanently dealt with, even by an amateur, so long as they actually pay attention to some rational facts.

The only two stands I know of here, one is in a grand estate, the other rather spread out, owing to the efficiency of the..... Environmental Protection team at our local Council, who've actively and physically spread it over a few hundred metres with their ditch-tidying!

Freecall: Love it! :rotfl:

firesidemaid

One thing to remember is that your mortgage or that of future buyers may be affected - you really do need to take legal advice. Some lenders will give mortgages on known Jk properties, but require specific & expensive treatment plans & Certificates/Reports to do so.

We lost a purchaser for our house due to the fact that Jk was found in school grounds behind the house of said purchaser. Their buyer's lender would not lend. We lost out as the next buyer of our house paid us 5K less.

Davesnave

firesidemaid wrote: »

One thing to remember is that your mortgage or that of future buyers may be affected - you really do need to take legal advice. Some lenders will give mortgages on known Jk properties, but require specific & expensive treatment plans & Certificates/Reports to do so.

If the OP has a mortgage, the JK is more than 7 m from the house, so that's unlikely to be affected or withdrawn. As the previous owners probably didn't disclose, it's a fine judgement whether to give the house a 'JK history,' or just deal with it.

In 5 years there should be nothing to disclose anyway, but there is at least one neighbour willing to talk on the subject!

martindow

Isn't the problem with JK that it is probably in neighbours gardens as well? Unless everyone deals with it, the plant will inevitably return - JK doesn't respect boundaries and fences.

Davesnave

martindow wrote: »

Isn't the problem with JK that it is probably in neighbours gardens as well? Unless everyone deals with it, the plant will inevitably return - JK doesn't respect boundaries and fences.

Yes, it can be a problem like that, but we don't know that it is in this instance, so there seems little point in speculating.

cajef

DaftyDuck wrote: »

It's this "Garden will never be 'normal' again - sue everybody or kill the previous owner "carp that bothers me! Spreading panic and discord rather than a bit of rational fact and calm. Knotweed is easily and permanently dealt with, even by an amateur, so long as they actually pay attention to some rational facts.! :rotfl:

Could not agree more, one person keeps posting and scaremongering in every JK thread that is started on these forums with lots of misinformation and second hand waffle that they have read or allegedly been told by so called experts.

I have also had personal experience of JK and have successfully treated it and eradicated it over several years using over the counter treatment and chemicals.