Last night’s BBC One Show reported about a terrible situation where a couple have discovered Japanese knotweed growing up through the floors in their house, the same story reported in the Daily Mail on the 23rd of October. No doubt some knotweed removal companies will use this as an example that Japanese knotweed can spread under buildings and destroy them, however, this is not the case. The house has been built on top of an infestation of live Japanese knotweed. How can we be sure that the Japanese knotweed did not spread under the building? The Japanese knotweed would spread into the open area of the garden, the path of least resistance, before it would spread under a house. It needs light to survive so why would it spread into the darkness below a house rather than the garden?
It’s good that the BBC are helping raise awareness of Japanese knotweed although it is unfortunate that it is under these circumstances. The family have been so badly affected by this invasive weed that it has made it into mainstream news when it could have been prevented from happening if the developer had appointed a qualified company to rid the site of Japanese knotweed before the house was built.
Also, it would have been good if the BBC had given accurate information about the treatment options for Japanese knotweed, rather than a pessimistic outlook (was it scaremongering?) by saying that it may require digging down 3 to 5 metres to remove the knotweed or a 3 to 5 year herbicide treatment programme. Similarly, when describing the appearance of the Japanese knotweed, it was described as looking like bamboo in October. This year, the knotweed is still in full leaf in October! I know I am being picky but surely it would have been more useful to quickly show some photos of Japanese knotweed to help people recognise it and prevent situations like the one reported from happening in the future.
IWA. Getting to the root of the problem.