The Evolution of Japanese Knotweed

Japanese knotweed is from places like Japan and China, even parts of Russia as well. Throughout its native range, there are some kind of forces that keep it in check. These include things like volcanoes, for example, which is why we can't really kill it with fire in the UK. A single foliar application of glyphosate once a year was the most effective way of controlling Japanese knotweed - now supported by Welsh Government.