Japanese knotweed heatmap populated with over 50,000 infestations in first year

26 February 2020: A live Japanese knotweed heatmap that launched just twelve months ago has already been populated with almost 52,000 infestations, highlighting the extent of the Japanese knotweed problem faced across the UK.

Exposed: The Japanese Knotweed Heatmap, created by Environet UK, is the most comprehensive live record charting the spread of the UK’s most invasive plant. A valuable resource for property professionals involved in residential transactions, including developers, surveyors, conveyancing solicitors, mortgage lenders and estate agents, Exposed provides a snapshot of the local Japanese knotweed situation and helps assess the level of risk posed to a property or site.

Over 93,000 postcode searches have been undertaken in Exposed’s first year of operation, whereby users can enter a postcode to discover the number of reported knotweed sightings nearby. Hotspots are highlighted in yellow or, in the most severe cases, red, with areas such as South Wales, Bristol, Bolton and London among the worst affected.

Following recent changes to the wording of the Japanese knotweed question guidance on the TA6 form completed by property sellers, which will result in higher numbers of “Unknown” responses, buyers will be reliant on their own investigations to determine the risk of a property being affected. Exposed will give them an indication of the extent of the problem in the local area and if a high number of knotweed sightings appear nearby, they may choose to instruct a Japanese knotweed survey to check the likelihood of the property being affected or at risk of encroachment from infestations in the vicinity.

Nic Seal, Founder and MD of Environet, who created the heatmap, said:

“We’ve had an incredible response to the launch of Exposed, with over 100,000 visits during the first year and 93,000 postcode searches. This just goes to show the thirst for information about Japanese knotweed and the need for credible resources to help property professionals and their clients assess risk during the buying and selling process.

“High risk results should always prompt further investigation with an on-site Japanese knotweed survey, in order to give the buyer as much certainty as possible.”

Japanese knotweed has spread rapidly across the UK since its introduction to the UK as an ornamental plant in the 1840s. It is notoriously difficult to treat and can impact a property’s value by up to 10%. Environet’s online valuation tool, JK-VIM, enables surveyors, estate agents and property owners to check how much the value of a property may potentially be reduced if it is affected by knotweed. It also offers revised valuations if a property is treated by herbicide or excavation and if it has a ten-year insurance-backed guarantee for the works.


Kindly shared by Environet UK