September 25, 2014

Japanese Knotweed is an invasive species of plant which can cause damage to properties if left untreated, particularly with drains and other buried services, paths and driveways,boundary/retaining walls, outbuildings, conservatories and gardens.

Japanese Knotweed begins to grow in early spring and can grow in any type of soil, no matter how poor. It can grow as much as 20 centimetres per day, and can reach a height of 1.5 metres by May and 3 metres by June. It does not produce viable seeds in the UK, but instead spreads through rhizome (underground root-like stem) fragments and cut stems. Japanese Knotweed:

• produces fleshy red tinged shoots when it first breaks through the ground
• has large, heart or spade-shaped green leaves
• has leaves arranged in a zig-zag pattern along the stem
• has a hollow stem, like bamboo
• can form dense clumps that can be several metres deep
• produces clusters of cream flowers towards the end of July
• dies back between September and November, leaving brown stems

Historically, methods of treating Japanese Knotweed have varied in success. As a result, Japanese Knotweed has caused some problems in the residential housing market because of the concerns about the damaging effects of the plant.

Mortgage lenders will expect the presence of Japanese Knotweed to be noted on a residential valuation report. RICS Red Book guidance requires the valuer to indicate the presence of ‘invasive vegetation’.

There is no blanket policy from Mortgage lenders which prevents them from lending on properties which have Japanese Knotweed, although the difficulty in treating Japanese Knotweed has seen some historical reluctance to lend. Individual lenders will take into account a range of factors when considering when to lend on a property, taking into account the specific circumstances and some lenders consider applications on a case-by-case basis. Where remediation works are being implemented to remove Japanese Knotweed, generally lenders look for evidence of an initial treatment together with a commitment for ongoing treatment programme.

There are a variety of methods were used to treat Japanese Knotweed, with varying degrees of success. The Property Care Association, which has members who treat invasive plants, has formed a group which seeks to provide a set of standards for treatment to lessen the risk for homeowners, lenders and insurers. This group has worked with RICS, to publish an information paper which is designed to provide information and explanation to RICS members about Japanese knotweed. In  addition the Property Care Association have published a Code of Practice. It is hoped that this will, over time, provide appropriate assurances for lenders and homeowners who own, are looking to purchase, or lend on, properties which have Japanese Knotweed.

Should you have any queries about the contents of this article, please do not hesitate to contact Janet Knox, Paralegal, Cleaver Fulton Rankin on 028 9027 3141

Please note; the content of this article is for information purposes only and further advice should be sought from a professional legal advisor before any action is taken.
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