Japanese knotweed is an invasive species of plant that has plagued the UK for several decades. The pernicious weed is bamboo like in its structure with thick walled, but hollow stems. In the winter, it dies back into the ground but it rapidly grows up to 2.1m in height in peak summer creating a dense, but admittedly aesthetically pleasing foliage. It can be self spreading, but it's rhizomes can also be carried on trains, along canals and even in garden waste. It has been clai