Thankfully, Japanese knotweed is not harmful to humans or animals. For information specific to the activity of resveratrol, see … Then you should let them know about Japanese Knotweed Specialists, one of the UK’s leading contractors and consultants in the control, treatment, removal and thorough elimination of Japanese Knotweed and that they can contact us here or give us a call on 0800 122 3326. Check out our article on, Smith v Line: The cost of allowing Japanese Knotweed to spread, The Grounds Care Group Acquires Japanese Knotweed Management, Read about Japanese Knotweed in FMUK magazine, Building Engineer Magazine publishes article on Knotweed, The consequences of letting Japanese Knotweed spread. Over many years, Japanese knotweed has acquired a reputation as one of the most invasive plants, and has been blamed for causing damage to properties. Only between 2% and 6% of respondents reported any co-occurrence of Japanese knotweed and structural damage to buildings. It’s possible for Japanese knotweed to damage the foundations of a house, but this will only happen when infestations are long-established and there are already weaknesses in the building. Japanese Knotweed (sometimes spelt Japanese Knot weed) is a non-native, alien invasive plant species, originally from Japan & Northern China and it was first introduced to Europe in the 19 th Century.. Japanese Knotweed was first introduced to Britain by the Victorians as an ornamental plant – and was actually awarded a gold medal at a prestigious flower show. Japanese knotweed is an invasive plant, known to cause significant damage to structures and being notoriously tricky to get rid of. The neighbours complained about the encroachment on to their land, and were awarded damages when the judge ruled Japanese Knotweed as a natural hazard affecting landowners’ ability to fully use and enjoy their property. Typically blooming between late summer and early autumn, Japanese knotweed flowers are a distinct creamy white colour and form in clusters of up to 10cm long. This is why mortgage lenders take it seriously. Basically, if water can drain down into it, Japanese knotweed can grow up through it. It can also create a fire hazard in the dormant season. Japanese Knotweed is also “invading” New Zealand, Australia, and Tasmania. Vigorous stands of Japanese knotweed that are left to grow will overwhelm lightweight, unsubstantial and poorly built outbuildings/garages and garden sheds, greenhouses etc. It is difficult to control once established. Typical damage from Knotweed includes damage to tarmac and paving. The law states that we can store cookies on your machine if they are essential to the operation of this site but that for all others we need your permission to do so. Apart from the fact that Japanese knotweed can cause severe damage to your property, it can also affect the ability to sell your home, obtain a mortgage or property insurance. If you have been affected by Japanese Knotweed damage, or you have bought a property without being warned of the potential for Japanese Knotweed infestation, we can help you claim compensation. You can customise your browser's cookie settings if you wish to manage your cookie security. Japanese Knotweed Damage to Property. In the UK, Japanese knotweed is widely believed to pose a significant risk of damage to buildings that are within seven metres of the above-ground portions of the plant – the so-called ‘seven metre rule’ – due to its underground shoots, known as rhizomes. Japanese Knotweed Damage to Drains and Other Buried Services. A case earlier this year between two neighbours was resolved after thirteen years, when a judge ruled Ms Line had allowed Japanese Knotweed to encroach onto the Smith’s property and as a result the value of the claimants’ land had been reduced by 10%, from £800,000 to £720,000. What you mustn’t do is ignore it, especially if it’s within your property boundaries. Large, densely packed roots and rhizomes of Japanese knotweed can disrupt drain runs. During the summer months, Japanese knotweed can grow up to 10cm every day and up to 10-12 feet high. Once knotweed has spread under your house, it can exploit small access areas and invade your home. The mass of the stands can ‘push over’ retaining walls/fences, often resulting in sudden collapse. If you’re thinking a plant can’t do much damage to your home you couldn’t be more wrong. Knotweed roots can exploit existing cracks and gaps in the pipes in their search for water, which will further damage and, in some cases, block the drains. Phone: 0333 2414 413. Middlesex, It helps to ensure the plant will rebound if damage to the shoots occurs. Japanese Knotweed grows rapidly – up to 10cm per day and has strong binding roots that ‘knot’ together. Ms Line was ordered to employ reputable contractors over the next five years to eradicate the agricultural interloper and also to pay court costs. Japanese knotweed can also seriously damage buildings, hard surfaces and infrastructure in some cases. Even if it does not cause any damage, just allowing Japanese Knotweed to infiltrate another garden is enough cause for legal action. Irish ecologist says threat posed by Japanese knotweed vastly overstated In the UK the weed is widely believed to pose significant risk of damage to buildings within 7m of the above-ground portions However, despite the plant’s fearsome reputation, there can still be some confusion as to what it actually does. SO51 7JF, T   0333 2414 413 What Does Japanese Knotweed Really Do? Ever eager to expand its territorial domination, Japanese Knotweed weed will infiltrate the tiniest of cracks and wind its wily way through drains and underground sewers. – With its insatiable thirst, Japanese Knotweed will worm its way into pipes through tiny cracks or joints, and from there it will expand locking the pipe and eventually breaking it. But a small clump growing some distance from your house should be a perfectly manageable problem. During the late summer, it can also be identified by its creamy-white flowers. According to 2016 cost estimates from the Rockingham County Conservation District (RCCD), the typical cost to manage knotweed using a glyphosate based product is approximately $500/acre for Our expert Japanese Knotweed solicitors can help you make a claim to: 1. Failure to control it could also lead to a substantial fine or even prison, so this is not a problem that should be taken lightly. Because of their pesky impacts, wild parsnip and Japanese knotweed are defined as prohibited noxious weeds in Minnesota and were chosen for this research. Failsworth, Manchester, Knotweed’s strong, robust plant structure means it can thrive in a wide range of growing conditions. In the search for moisture, Japanese Knotweed can damage structures, underground water and gas pipes. Can Japanese Knotweed damage buildings? Wild parsnip is a harmful invasive plant in North America. Japanese Knotweed began its UK staycation in the 1850s when it wowed Victorian botanical with its exotic appeal and was a welcome guest in any well-to-do garden. Japanese Knotweed. Japanese knotweed can also seriously damage buildings, hard surfaces and infrastructure in some cases. You’ll know Japanese Knotweed by its spade-shaped leaves, which can grow up to five and a half inches in length. If Japanese knotweed grows close to your house, retaining/garden wall, fence or garden building, the underground roots and rhizomes can damage these structures as they exploit the cracks/mortar joints and weaknesses. Room 5, Television House, – Again is left unchecked, Japanese Knotweed will grow with enough force to damage fences and even cause walls to fall. Installed underground to prevent damage from tree roots, Japanese Knotweed and other invasive plant species, to underground services and existing structures. At its worst, Japanese knotweed can cause significant subsidence to your property, especially if the property has weak points for the knotweed to exploit. Japanese Knotweed was introduced to the UK by botanists in the 1850s. Laboratory tests suggest the leaf fleas – Japanese knotweed psyllids, or Aphalara itadori–can kill young shoots and potentially stop the plant growing by sucking up its sap. Google Analytics uses various cookies in order to function. Japanese knotweed has come a long way since Philipp Franz von Siebold, the doctor-in-residence for the Dutch at Nagasaki, brought it to the Utrecht plant fair in the Netherlands in the 1840s. Japanese knotweed can grow up to 10cm per day, and because of this rapacious growth, it has been known to cause damage to building structures and substructures by targeting weak points, such as cracks in masonry, and attempting to grow through them. Also, cookies make the interaction between you and our website faster and easier. The Japanese knotweed psyllid should offer relief against the rampant Asian knotweed. Closely packed stands can undermine garden walls with shallow foundations and old or poorly constructed fences. Sep 8, 2015 - Explore Wise Knotweed Solutions's board "Japanese Knotweed Damage" on Pinterest. Suzanne Lommen of the Institute of Biology Leiden is coordinating the field trials as part of a consortium which includes CABI, Leiden University, Koppert Biological Systems, Probos, STOWA and the Pest Species Work Group of the Dutch Water Authorities. Infamous for its devastating ability to cause costly damage to property, Japanese knotweed is the most widespread form of knotweed in the UK. – Japanese Knotweed will grow up and through vents and air bricks two metres above ground, and once it’s in cavity walls it has the force to push the two skins of the wall apart. and in the worst cases can even cause subsidence. Schedule 9, Section 14 of the Wildlife and Countryside Act 1981 states that “if any person plants or otherwise causes to grow in the wild any plant which is included in Part 2 of Schedule 9, he shall be guilty of an offence”. You’ll know Japanese Knotweed by its spade-shaped leaves, which can grow up to five and a half inches in length. 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