Is this the dreaded Japanese Knotweed!! Ident and advise required

in Talkback
Hi, I have just come across this in a garden, have I correctly identified it as Japanese Knotweed, if so what is the next course of action as gardeners are not yet allowed to chemically treat it.
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Need to see the leaves Paul.
hmm, it doesn't have any on at the moment.
Has a resemblance to Leycesteria formosa.
But as artjak says, we need to see the leaves. Shape of the whole plant and its base would be good as well
In the sticks near Peterborough
Don't think it's Knotweed - the dreaded JK has shoots and leaves growing alternately from each side of the stem - yours looks as if the shoots are growing in pairs.
Are there any leaves we can have a look at?
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Dove, do you know if JKWeed has slightly reddish stems?
dont look like it https://www.google.co.uk/search?q=japanese+knotweed+identification&sa=X&espv=210&es_sm=122&tbm=isch&tbo=u&source=univ&ei=FcodU5uRNYOM7AbFwIHABA&ved=0CEkQsAQ&biw=1366&bih=643 i know its long but ??
..nothing like Knotweed... might be Fennel..?
Paul, where did you hear that gardeners cannot chemically treat it?
I think the stems are a bit redder on JK. Is there a lot of it Paul, and what sort of height is it just now?
I live in west central Scotland - not where that photo is...
Yes leycesteria formosa does look familiar in the photos but so does JK. Does leycesteria formosa have multiple stems at the base like Japanese knotweed, she said that she thought a neighbour had some JK a while ago.
Ah well spotted DFA, so JK does not have leaves in pairs. Ok so I think we might be onto something. I might have to go back to get more photos, I shall take photos of the base, any leaves and stems.