Fallopia japonica, more commonly known as Japanese knotweed, has been the source of both financial and emotional stress for property owners and developers for years.
Introduced from Japan as an ornamental plant by the Victorians, it can be identified by its bamboo like shoots, leaves of around 14cm and creamy white flower tassels. It is notoriously hard to eradicate, fast growing and often costs thousands to treat. It is estimated that eradication cost per year, in the UK, is above the £1.6 billion mark.
Though it is a crime under the Wildlife and Countryside Act 1981 of plant Japanese knotweed, it is not illegal to have Japanese knotweed growing on your property.
That said, if it spreads to neighbouring land, and if you are aware of it and fail to do all you reasonably can to rectify the situation, you may be liable to neighbouring landowners for private nuisance, and/or you may become the proud recipient of a ‘community protection notice’ issued by the local council under the Anti-social Behaviour, Crime and Policing Act 2014.
In a relatively recent case, involving Network Rail, two adjoining bungalow owners in Maesteg, claimed they were unable to sell their property due to uncontrolled Japanese knotweed growing from a bank of land owned by Network Rail.
Though the knotweed had not yet damaged the foundations or any other parts of the bungalows, it had significantly reduced the marketability of the properties. Both claimants sought compensation for the loss of value of their properties.
It was decided that, though no physical damage had occurred, the stigma surrounding the weed and the resulting decrease in market value was enough to warrant a claim.
Network Rail’s delay in treating the knotweed, while being aware of the neighbours concern, was enough to establish liability. Both claimants were awarded £10,000 to reflect loss in property value, a further £4,320 for treatment and £350 per year general damage award for loss of amenity of their land.
Though the case was won by the claimants, the damages awarded were significantly less then what was being originally claimed, and would therefore realistically act as no real deterrence for national rail to remedy the overarching problem of knotweed growing on their land. This should therefore be considered when purchasing land near railway embankments.
It is important to note that the Council of Mortgage Lenders stated it is highly likely mortgage providers policies are influenced by issue. If knotweed is present, it is usually a significant factor the lender will consider, along with the level of severity and chance of successful removal, when deciding to grant mortgages. Even if mortgage lenders agree to lend on an affected property, they will normally require evidence of treatment that will eradicate the plant as a condition of lending.
The issue of knotweed also extends to insurance with the Association of British Insurers highlighting the problems knotweed poses to insuring properties and therefore the effect on market value.