Monday 25 July 2016

Japanese knotweed: Aphalara itadori to the rescue

Councillors in the 'noughties will recall that after dog droppings, speeding motorists and unauthorised parking, the biggest complaint in their casebook was Fallopia japonica (or Polygonum cuspidatum or Reynoutria japonica - even its botanical name was a nuisance), aka Japanese Knotweed. Virtually indestructible by normal methods, any bit with two ends can lead to a fresh infestation. Hence, it is legally treatable only by certificated specialists. It does not make the headlines as it used to, but it is still a pest plant.

I was just getting to the end of my term as councillor when the first announcement was made of a possible biological control. The plant-louse aphalara itadori was identified as one of the few bugs which would eat the knotweed and, better still, appeared to specialise in it, so that there was not likely to be any collateral damage as with previous releases of intended biological controls (look up "cane toad"). Still, there needed to be extensive trials in a closed environment to be certain. It seems these have now concluded successfully and live releases, including some in south Wales have started.


4 comments:

Stan said...

I've always said that whoever comes up with the solution to Japanese Knotweed will become rich beyond people's wildest dreams but if it's an insect that's the answer - how can you patent that? Come to think of it - I'm not sure a louse is an insect. Interesting post though and one I'll pass on to people I know who suffer from the stuff and tried all ways to get rid of it - unsuccessfully.

Frank Little said...

To be specific, psyllids' English name is "jumping plant-lice" and they are insects.

I suppose you can make a living by knowing how to deploy the bug to best effect, but I am rather glad that it is one natural thing that looks like it cannot be patented. Mind you, if someone dreams up a genetic modification that makes it more effective ...

Stan said...

Thanks for the correction, Frank. Don't know how I ever got that idea unless it's the association with the crab louse, which is an insect but crabs have more than 6 legs. I'll have to go back to school and retake Biology!

jeff3 said...

hmm this had come up a good few yrs back trials it seems for this dreaded weed lets hope it does whot they say has many households have lost out to this weed