One Single Plant,

has caused devastation in the UK,

in the 1840s Bavarian plant importer Phillipp von Siebold brought one plant to the Utrecht plant fair in the Netherlands in the 1840s, no one imagined it would end up becoming a global threat, it was prized for its beautiful flowers and advertised as an ornament, medicine, wind shelter, soil retainer, dune stabilizer, cattle feed, and insect pollinator, despite records of gardeners expressing their concerns about the plant’s invasiveness, it was sold across Europe for almost a century, and by the time everyone realized the monster we had released, it was too late to do anything about it, Von Siebold sent a single plant to Kew Gardens in London in 1850, and it was the descendants of that one plant that managed to colonize most of the British Isles, in 2000, biologists analyzed 150 samples from across the U.K. and concluded that they were all clones of the same plant Von Siebold sent over a century ago, the DNA was identical, which technically meant that the UK had been conquered not by a species, but by a single plant, the plant is Japanese knotweed, (Reynoutria japonica, synonyms Fallopia japonica and Polygonum cuspidatum),

here is the problem, British banks will not issue a mortgage to a property infested with knotweed or with the invasive plant nearby, without an expensive plan to control the plant, Japanese knotweed growing less than seven meters from a structure is considered unacceptable by many mortgage companies, because it’s assumed the plant’s underground shoots (rhizomes) can cause structural damage, and it is almost impossible to get rid off, because of its ability to asexually reproduce, a new plant can grow from a piece of root just an inch or so long, and its shoots form intricate underground networks that are nearly impossible to remove completely, walls, roads, or other types of obstacles do nothing to prevent its advance, because the plants roots can reach up to 70 feet from the plant itself, to be sure every bit of root is eliminated from a property, one would have to dig three feet deep and completely dispose of that top layer of soil in a specially designated landfill, which can be both expensive and time-consuming, 

it has become such a problem in the UK that you can download a telephone application to see how near you are to reported knotweed infestations, of course if your area does not appear, the weed could still be nearby, just not yet reported, (you can download PlantTracker app: IoS phones here; Android phones here), the obvious question is why is this weed not a problem in Japan? the answer is that in Japan a small insect eats it, the Japanese knotweed psyllid, (Aphalaris itadori), the insect feeds on this plant and can easily keep it under control, however, efforts to have it introduced in other areas, such as the UK and United States have not been as successful as many had hoped, in the US, getting the insect approved by the Animal and Plant Health Inspection Service has been a slow process, and in the UK results have been mixed, the problem with introducing a new species in a completely new environment is that you have to take into consideration native predators, for example, in certain areas in the UK, anthocorids feasted on psyllid eggs, preventing them from reproducing in sufficient numbers, still, experts are hopeful that the tiny knotweed eaters will be able to at least control the spread of the plant and make it possible for other plant species to compete, how amazing that just one single plant could spread so much as to cost it is estimated £1.6 billion to eradicate!