I reached the town of Maesteg, in Wales, where the weed was first reported in the wild, late in the afternoon. I had seen so much of it already that day, and in such calm profusion, that I was no longer sure what I was expecting to find in the place of its original escape. Since it breached the redbrick walls of the Royal Botanic Gardens at Kew, in West London, at some point during the 1850s, Japanese knotweed has colonized pretty much every corner of the British Isles, but nowhere with more assiduity than the wet valleys and…
Battling Britain’s most destructive invasive plant