Japanese knotweed kills house prices
According to the Telegraph, house sellers have been forced to spend thousands of pounds eradicating Japanese knotweed from their land after finding their homes had become virtually unsellable because potential buyers were being turned down for mortgages.
Lenders claim Japanese knotweed, which is capable of pushing through concrete, poses a risk to the structure and fabric of the building, and so reduces the value of a property.
Mortgage lenders are now beginning to insist that they will approve an application only if the Japanese knotweed on the property is removed and the homeowner obtains a written guarantee from the environmental control company to say it has been eradicated.
Japanese knotweed first escaped into the British countryside in the mid-19th century after being brought over from Japan as an ornamental garden plant.
The plant normally grows in the poor, rocky soils and on the slopes of volcanoes in Japan. Without natural pests and diseases, however, Japanese knotweed has become highly successful in the UK and it is capable of regenerating from just a tiny fragment.
The bamboo-like stems, which grow up to 12 feet tall, can push through concrete and can damage buildings. Japanese knotweed also has an extensive underground root system, called a rhizome, which make it difficult to destroy with herbicides.
This makes Japanese knotweed extremely difficult and expensive to eradicate from an area as the roots often need to be completely dug up and the contaminated soil disposed of. Cheaper herbicide spraying can be used provided the soil is treated.
Japanese knotweed is now so prevalent in the UK that according to official records there is now not a single 6 mile square in the country where it is not present and it is only considered to be absent from the Orkney Islands.
A spokesman for Santander, the country’s biggest mortgage provider through its ownership of Abbey and Alliance & Leicester, said:
“Due to the invasive and destructive nature of Japanese Knotweed, if the weed is found in close proximity to the property we would need to assess whether or not a mortgage could be accepted.”