Japanese Knotweed (Fallopia Japonica) is a fast-growing and invasive plant. It can grow anywhere, has distinctive red stems and flat leaves. It can reach heights of up to four meters and its roots can stretch three meters deep and extend around seven meters in all directions.

Japanese Knotweed damage can be severe. It is very difficult and expensive to remove once it is on your land. Even if the smallest piece of root is left in the soil the weed can regrow very quickly. Its root system is very strong – strong enough to break through concrete and it can cause serious damage to buildings and drainage systems if not kept under control.

It was first introduced to Britain in the 19^thCentury as an ornamental plant but has since been allowed to grow wild. Matters have been made worse as certain companies such as Network Rail have actively planted Japanese Knotweed to sure up embankments and other areas of land.

As Japanese Knotweed can grow anywhere it tends to spread through large areas of land that haven’t been looked after by their owners. These sites can include railway tracks; rivers; construction sites etc. If your property is close to areas like these then you could be at greater risk from the spread of knotweed.

Why is Japanese Knotweed dangerous?

Japanese knotweed can cause severe problems for homeowners. Not only is there a potential risk to losing your garden to an infestation, it can also cause problems to your home’s foundations and create potential issues further down the line when you come to sell your house.

Even if the Japanese knotweed hasn’t caused physical damage to your property it can seriously reduce the value of your property – leaving it is simply not an option because of the future damage it will cause. Our panel are aware of several instances were mortgage companies won’t lend money against a property affected by Japanese knotweed.

This can mean that you are unable to sell your house or you are only able to sell your house at an undervalued price. Our panel of Japanese knotweed solicitors have also heard of cases where surveyors have valued a property at zero because of the effects of Japanese knotweed.

How does Japanese Knotweed spread?

The Japanese Knotweed plant is very fast growing within soil, from a fibrous rhizome – a creeping root system. Soil can be contaminated with reproductive knotweed material from a depth of 3 metres, with a radius of 7 metres.

In most cases, the accidental transportation of soils containing Japanese Knotweed seeds means that it then takes over whatever soil it is placed into. In addition to this, with the plant not being native to the United Kingdom, the usual natural controlling systems and organisms that have occurred in Japan over many years are not present, meaning it is left unchecked to grow.

In most of the Japanese Knotweed compensation claims, our group of solicitors are dealing where the Japanese Knotweed has spread from commercial land, such as railways and construction sites, onto residential land. In these cases, our panel have argued that the owner of the residential land has an actionable claim against the owner of the neighbouring land for damages.

If you have Japanese Knotweed on your property, or if there is Japanese knotweed close to your property, our panel of solicitors can help you claim compensation. The scenarios they are currently involved with include:

1. Japanese knotweed has spread onto your land because another landowner hasn’t controlled it on their land. This might be a neighbour or a larger organisation like Network Rail. In such a case you may have a claim for damages.
2. You have purchased a property, but the seller has failed to tell you that they had a problem with Japanese Knotweed. In these cases you would have a claim against the seller.
3. You have purchased a property and obtained a home buyers survey. It subsequently transpires that the property had knotweed, but the surveyor failed to pick this up. In these cases, you would have a claim against the surveyor.

In the above cases, our expert Japanese Knotweed panel can assist. They would bring a claim for Japanese Knotweed damages which would comprise the cost of eradication and removal as well as any diminution in value of the property.

What Does Japanese Knotweed Look Like?

Japanese Knotweed can go through a few recognisable phases throughout the year. During Spring, purple/red stalks will appear in ground. These will then sprout into green-ish asparagus-like spears which can grow up to 8cm a day in the warmer months of spring.

Moving into summer, these stalks will start to form thick stems which develop broad, heart-shaped leaves. The leaves produce a distinctive alternating pattern along each side of the stem. In early summer, these stalks can grow up to 3 metres in height.

Japanese knotweed flowers are also a giveaway. They emerge in late summer and are cream coloured. They form in cluster formations.

The Japanese Knotweed Key Legal Case – Williams and Waitsell v Network Rail

As determined by the Court in the decision of Williams and Waitsell v Network Rail, owners have a duty of care to ensure that Japanese Knotweed does not spread from their land. Even in cases where no physical damage has been caused the Courts have found that neighbours can be liable for loss of amenity value due to the Japanese knotweed, or the presence of the plant’s roots under their property.

The Courts have made it clear that landowners must take reasonable steps to prevent or minimise the spread of Japanese knotweed across the boundary. Whether a defendant has taken ‘reasonable’ measures is determined on a case by case basis, but at first instance the Court determined that the mere presence of knotweed on someone’s land could lead to a successful nuisance claim from neighbours whose property value was diminished because of the knotweed.

In the case of Williams and Waitsell v Network Rail, the Claimants owned bungalows next to land on which grew a large stand of knotweed. The land was owned by Network Rail, who had carried out sporadic herbicide treatment to the knotweed, but no comprehensive Japanese Knotweed treatment plan ensuring the thorough removal and destruction of the plant. The claimant argued that they had an encroachment claim against Network Rail in so far as Japanese Knotweed roots had spread underneath the properties; and a quiet enjoyment/loss of amenity claim on the basis that the presence of Japanese knotweed on network rails land was a serious interference with the quiet enjoyment or amenity value of their properties.

The Court did not agree with the encroachment claim, stating that while the presence of the rhizomes under the claimant’s properties was established, a claim in nuisance for encroachment required some physical damage. In this case the Court found no damage to the properties or any change in the soil structure.

The Court, however, found in favour of the Claimants in connection with their claim for quiet enjoyment/loss of amenity. The Court went on to assess whether Network Rail had breached a duty of care and caused the diminution in value. The Court held that Network Rail had breached a duty of care and caused the diminution in value. He held that network Rail had sufficient constructive knowledge of the presence and risks associated with Japanese Knotweed, and that it had not done all that was reasonable to prevent or minimise interference with the claimant’s use and enjoyment of their properties.

Network Rail appealed against the County Court decision, on the following grounds: that the Court had been wrong to say that, where a homeowner suffers diminution in the value of their property because of the presence of knotweed, the pure economic loss suffered constitutes an actional private nuisance on the basis that it interferes with the quiet enjoyment of their property; the court had been wrong to find that there was a casual link between National Rail’s breach of duty and the diminution in value of the claimant’s properties.

The Claimant added further reasons for upholding the County Court judgement: and encroachment without physical damage can give rise to an actionable claim in private nuisance and the presence of Japanese knotweed roots and rhizomes on the claimant’s properties constituted damage in any event.

The Court of Appeal took a slightly different view. The court made it clear that the claimant’s right to let out his property or sell it for capital gain would not be included in a particular piece of land’s amenity value. The judge was of the view that the purpose of the tort of nuisance was not to protect the value of a property as an investment or financial asset, but to protect the use and enjoyment of the land ‘as such’. The Court of Appeal held that the Court had been wrong to find that the presence of knotweed was an actionable nuisance because it diminished the market value of the claimants’ properties. The purpose of the tort of nuisance was not to protect the value of property as an investment – it was to protect the landowner in their use and enjoyment of the land. The court’s decision extended to the tort of nuisance to a claim for pure economic loss and this would be a radical reformulation of the purpose and scope of the tort.

The Court of Appeal, however, upheld the original court judgement based on the claimant’s additional reasons. Network Rail’s knowledge of the presence of knotweed and its failure reasonably to prevent interference with the Claimant’s enjoyment of their properties were sufficient to give rise to a cause of action in nuisance. There was no reason why a Claimant should not be able to obtain a final injunction where the amenity value of land was diminished by the presence of rhizomes even though there was no physical damage at the time.

The Judge also disagreed with the County Court’s view that a nuisance claims on the basis of encroachment necessarily required ‘actual’ physical damage. He took the view that encroachment of Japanese knotweed rhizomes imposed an immediate burden on any owner of land wishing to develop it, making this a ‘classic example of an interference with the amenity value of the land’. Japanese Knotweed is pernicious and carried with it the risk of future physical damage and methods of eradication-imposed difficulties and increased costs for landowners wishing to develop their land. Encroachment of rhizomes on the Claimant’s land, in the context of constructive knowledge and failure to act reasonably by Network Rail, did constitute an actional nuisance claim.

As such, in private nuisance actions, Claimants cannot recover compensation to reflect (only) the fact that the presence of the knotweed has devalued their property in a purely financial or economic sense. Instead the critical question is to likely to be “…to what extent (in value terms) does the presence of the knotweed diminish the ability to use and enjoy the amenity of the subject property?”

How do I remove Japanese Knotweed?

Japanese Knotweed removal is no easy feat. It is a tenacious and sturdy plant that appears to just keep growing back no matter what action you take.

The first process of Japanese Knotweed treatment is cutting the stems down to the ground as far as possible. After this herbicide treatment on the stems can work, along with stem injection and potential excavation of the infected areas with machinery.

Once the plant seems to be gone, you will need to make sure the root has been eradicated completely. You will need to transport the Japanese Knotweed to an off-site burial which can be expensive. The plant is classified as “controlled waste” in the UK, so a sifting and screening service will remove fragments of the root and rhizomes from the soil.

Our expert panel would normally advise seeking professional Japanese Knotweed removal help. If you do have a Japanese Knotweed compensation claim, the cost of the removal will be covered by any compensation received.

How Claim Experts can help – Professional Japanese Knotweed Help

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, our expert panel of solicitors can help you claim compensation.

Our expert Japanese Knotweed advisors can help you make a claim to:

• Recover the cost to remove the Japanese knotweed in full by a professional
• Recover the cost to repair any damage caused
• Recover any potential loss in market value of your property

ClaimExperts's panel of solicitors can start your Japanese Knotweed insurance claim by claiming against the landowner responsible for the spread.

In addition to this, if the seller of the property failed to tell you about any Japanese Knotweed damage, or the surveyor missed it, they can help you make a claim against the person or company responsible.

How does No Win, No Fee work?

Our panel's Japanese Knotweed compensation claims work on a No Win, No Fee basis. This means that if our panel are happy that you have a potential knotweed claim, and you are unsuccessful in your claim, you do not pay any legal costs. 

If they are successful in your claim, they will deduct an agreed percentage of the claim from any compensation received on your behalf. This is a separate fee to the cost of any treatment or professional Japanese Knotweed removal costs.

This means there is no financial risk to you by carrying out a Japanese Knotweed claim.