Chesterfield tops 10 high-risk areas in Derbyshire for Japanese knotweed infestations

There have been 225 incidents of the unwelcome intruder in a 4km radius of Chesterfield, putting the area on top of the county’s table according to a heatmap produced by invasive plant specialists at Environetuk.

Japanese knotweed seeks out weak places, such as fractures in masonry, to grow and its roots can reach down to 20 metres underground. The plant can grow up to three metres high in spring and summer.

The plant destroys pipes and drains, weakens paving or building foundations and has the potential to lower the value of property by 5% to 15%, according to surveyor specialists at Stokemont.

Making a seller aware of the presence of Japanese knotweed has been a legal requirement since 2013. In London a man successfully sued the previous owner of his house after finding a large amount of the plant in his garden, resulting in a £200,000 court bill.

The top ten hotspots for Japanese knotwood in Derbyshire based on infestations within a 4km radius are as follows :

Chesterfield – 210

Derby – 202

Heanor – 175

Ilkeston – 161

Tibshelf – 158

Ripley – 128

Little Eaton– 120

Wirksworth – 104

Buxton – 97

Belper – 83

To check whether your area is infested with the plant, go to the website www.environetuk.com/exposed-japanese-knotweed-heat-map and tap in your postcode.

Should you find evidence of knotweed on your property, you should find a specialist company to treat it.

Spraying or injecting the stems with chemicals can be an effective treatment but only approved herbicides can be used.