Posted: 25/12/2013 at 08:29
Definitely knotweed, del. Perhaps I should clarify that I live in Switzerland and our waste disposal is different to yours. We do not have landfills here, only large incineration plants where all household rubbish except recyclables such as PET, newspapers, glass, etc. is burned in huge furnaces.
Ours crept across from neighbour who had bought it as a small plant. Sale of JN is now forbidden and there have been warnings to get rid.