Japanese Knotweed versus Aphalara itadori

[sometimes]

BBC NEWS | Science & Environment | Predators could be superweed fix

[sometimes]

I'm in two minds about this. On the one hand knotweed is a real pain, on the other I'm not happy about introduction of a pest. Have we not seen disastrous examples in other 'solutions'?

[handyman]

Hello Sometimes, must say I agree with you there.

It seems to be a British qwerk, that after creating the problem, be it Japanese Knotweed, Rhoddedrons or Signal Crayfish, et al, we always look for the cheapest or easiest way to eradicate it, usually with spectacular failure.

I cannot understand the logic of introducing another foreigner to our shores, if it is dependent on the original problem for its survival. All they can ever hope for is to control the problem rather than eradicate it.

In the case of Japanese Knotweed, as this has thrived and colonized much of the UK, in contrast to how it grows in its home country, by introducing this beetle, is it not likely to thrive as it has an unlimited food source?

It took me seven years to eradicate Japanese Knotweed from my garden, I just wish my neighbours were as conscientious! They are quite tolerant of my forays into their gardens to dig out roots and burn them.

Handyman

[sometimes]

I can see that areas of knotweed growth will become no-go areas because of clouds of flying beasties.
The research seems to concentrate on the relationship between Knotweed and Aphalara itadori. But what about our native species that might feed on Aphalara itadori - is it poisoness to them? Will they be a welcome food source for warblers? Answers of 'I don't know.' would mean we shouldn't do it.

[Rob_D]

You are worrying needlessly about introducing this new beetle. If it causes problems then we can just introduce something like a Cane Toad to eat it

Sadly it seems there are no easy answers. I am just hoping that one day we'll develop a really effective and foolproof solution to invaders (GM bacteria or Fungus perhaps?). Well done to Handyman for your efforts though.

[sometimes]

Originally Posted by Rob_D

You are worrying needlessly about introducing this new beetle. If it causes problems then we can just introduce something like a Cane Toad to eat it .

I think the song goes "" I know an old lady who swallowed a fly""

[tcvarlh]

True and look how the song ends
Why by all that's holy do we try to cure a problem be slapping a worse idea across it like a poultice?
What eats these psyllids? Do we have a predator here?

[Lancashire Lad]

The scientists say they have tested the beetle's feeding preferences on several "important" British food plants etc. and are satisfied that the insect will only go for the Knotweed.

However, they have not tested the insect's preferences on ALL British plants, so at best, they can only put this arguement forward as hypothesis based on incomplete data.

Even if these insects do prefer Knotweed, and manage to decimate it. (Presumably their numbers would have multiplied into the millions to achieve such a feat). What happens then?

Do all these insects conveniently die off? or do they turn their attention to whatever other British native plants take their fancy?

I remain entirely unconvinced of any merit in this proposal.

Regards
Mike.

[PMG]

Of course once they have eaten all the knotweed they are going to turn their tiny toes up and die for their country - job done and there again maybe they will discover a taste for ?wheat ?British orchids ?any and all home grown vegetables..... ?roses .......... grass??........Hmmmm.......

Pauline

[RobSutton]

Originally Posted by Lancashire Lad

The scientists say they have tested the beetle's ..........

It isn't actually a beetle but as someone higher up the thread has already mentioned it's a Psyllid. These are sap sucking insects and most are generally very host specific. This makes it a lot less likely to switch to other food sources than some other herbivorous insects. Could be it's the lesser of two evils, very hard to know until it's tried.