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Japanese Knotweed, A Legal Nuisance ‘’Knot’’ To Be Ignored

Japanese Knotweed, A Legal Nuisance ‘’Knot’’ To Be Ignored

Japanese knotweed has become an increasing problem in that its growth (it can grow at 20cm per day if unabated) has led to countless homes being devalued with the weed being present in the garden.

The knotweed was first brought to Europe from Japan in the mid-19th century by a botanist who found it growing on the sides of volcanos.  It was initially lorded for its beauty and was so celebrated that in 1847 it was named ‘’the most interesting new ornamental part of the year’’ by The Society of Agriculture and Horticulture at Utrecht in Holland.

In 1850 The Royal Botanic Gardens at Kew received a shipment of various plants which included a sample of knotweed.  By 1854 the plant had been sent to The Royal Botanic Gardens in Edenborough and was then sold commercially by nurseries.  The spread of knotweed, through purposeful planting and it escaping went undetected for years.

The issue with knotweed being a problem is that in its native Japanese volcanic landscape, the climate and regular deposits of ash keep knotweed plants small.  In Britain, without impediments it grows unabated and can even grow through concrete and tarmac with the roots going down to three meters.  Knotweed has no natural predators but it costs the UK economy 166 million pounds per year for treatment and in home devaluations.

What should homeowners be altered to?

Earlier this year a Court of Appeal judgment was handed down in the case of Williams and Wiastell against Network Rail Infrastructure Limited.  The Court of Appeal held that Network Rail was liable in nuisance for allowing Japanese knotweed to encroach onto the Claimants’ properties from its land adjoining a railway line.  The Claimants were awarded damages which included damages for diminution in value of their homes.

The ultimate question at the appeal was whether physical damage is required to establish a cause of action in nuisance.  The Court of Appeal held that the diminution in value itself was not a nuisance but the presence of Japanese knotweed was, and that the consequential diminution in value was recoverable in damages.  Diminution in value follows as recoverable as a consequence of such a nuisance.

This decision is an important one of which home owners should be cautious.  With diminution in value recoverable as a consequence of the nuisance it will be that a Claimant needs to establish just a nuisance before recovering diminution in value as a consequence of a loss of amenity.  Given the presence of Japanese knotweed will constitute a loss of amenity, it is simply a question of evidence rather than a legal principle as to whether there has been a diminution in value, and if so how much.

Therefore, homeowners can recover damages in respect of land blighted by Japanese knotweed.  Therefore do not ignore this weed on your land.  As well as the potential risk to your own home, you may also face an unwelcome liability to neighbouring homeowners.

If you have a query or would like to book an appointment please get in touch on 01256 320555 or email mail@clarkeandson.co.uk

Simon Horwood

Litigation Executive

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