Japanese Knotweed

Japanese Knotweed is an invasive non-native species which, having been brought to Britain as an ornamental garden plant in the mid-nineteenth century, is now established in the wild. It spreads quickly, crowding out native species and damaging their habitats, and is extremely difficult to control.

Under section 14(2) of the Wildlife and Countryside Act 1981, it is an offence to plant or cause Japanese Knotweed to grow in the wild.

However, there is no statutory requirement for landowners to remove these plants from their property once established naturally. 

Whose responsibility is it to control Japanese knotweed?

If the land is privately owned then the responsibility for the control of this weed rests with the landowner or tenant of the land. The Environment Agency or Worcestershire Regulatory Services are not obliged to control this weed on behalf of private landowners. Disputes between private landowners concerning the control of this weed are a civil matter.

Complaints concerning Japanese Knotweed growing on Council-owned land should be reported to Ron Evans via the Worcestershire Hub on 01684 862151.

The control and eradication of Japanese Knotweed growing on verges of large main roads (trunk roads) or motorways in the district is the responsibility of the Worcestershire County Council Highways Agency.

Q. I have Japanese Knotweed coming onto my land from private land adjoining property. What can I do?

A. The best solution is to co-operate with the neighbouring landowner and co-ordinate your control efforts, by sharing costs of labour or herbicide. If you do not know who owns the adjoining land or you are in dispute with your neighbour about the control of Japanese Knotweed then current legislation offers little support.

The Environmental Protection Act 1990 provides a remedy if Japanese Knotweed is causing a nuisance to private property. A private nuisance is defined as an "unlawful interference with a person's use or enjoyment of land, or some right over, or in connection with it" (Read v Lyons & Co Ltd. 1945). A solicitor or the Citizens Advice Bureau will be able to offer advice on how to take private nuisance action against a landowner where negotiations on control or eradication have failed.

Q. How do I control or eradicate Japanese knotweed on my land?

A. Regular cutting or pulling will, after a number of years, eventually exhaust the rhizome and kill the plant. It is important that all cut or pulled stems of Japanese Knotweed are kept on site and disposed of by proper composting or burning. Since the plant can regrow from even small fragments, all parts of the plant and any soil contaminated with it are classified as controlled waste and are required legally to be removed and disposed of by a licensed waste control operator.

Dense stands of Japanese Knotweed can be treated with a glyphosate-based herbicide, such as 'Roundup'. If the Japanese Knotweed is sparsely distributed, spot-treat or use 2,4-D amine, which is specific to broadleaved plants and will not harm grasses. It may take two or three years to completely kill the entire plant.

More effective control can be achieved if Japanese Knotweed is cut or sprayed in early summer, and then sprayed again in late summer before the winter dieback.

The use of herbicides in or near rivers, canals, lakes or drainage channels requires prior agreement from the Environment Agency.

In order to contact the Environment Agency on such matters, call their national communications centre on 08708 506 506. Herbicide application forms can then be sent out upon request.

For further advice on the control and eradication of Japanese Knotweed visit http://www.environment-agency.gov.uk/ and type Japanese Knotweed into the search box. You can also obtain the herbicide application form referred to above using the same search facility.