Japanese Knotweed: Weed Control

(asked on 7th July 2025) - View Source

Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, what steps his Department is taking to support landowners in (a) managing and (b) eradicating Japanese knotweed.


Answered by
Mary Creagh Portrait
Mary Creagh
Parliamentary Under-Secretary (Department for Environment, Food and Rural Affairs)
This question was answered on 11th July 2025

Defra recognises the impacts caused by invasive species, including Japanese knotweed. Japanese knotweed is listed on Schedule 9 of the Wildlife and Countryside Act 1981. This makes it an offence to cause Japanese knotweed to grow in the wild.

In England Government has developed guidance on how to prevent the spread of Japanese knotweed, as well as how to treat and dispose of it, which can be found on GOV.UK: How to stop Japanese knotweed from spreading - GOV.UK.

Recognising the limitations of manual removal Defra, in partnership with the Welsh Government and Natural England, is funding scientists at the Centre for Agriculture and Bioscience International (CABI) to conduct biological control (biocontrol) research into the use of naturally occurring, living organisms to tackle Japanese knotweed and other invasive, non-native plants. Biocontrol could provide a more cost- and time-effective way of managing these invasive plants. This research has identified the psyllid (a sap-sucking insect), Aphalari itadori, as a biological control agent for tackling Japanese Knotweed. Information about the research can be found on CABI's website.

Defra is providing funding for land managers to control and manage Japanese knotweed and other invasive plant species through the Environmental Land Management (ELM) Countryside Stewardship scheme. Further information can be found on GOV.UK: Countryside Stewardship Higher Tier actions - GOV.UK.

Defra is not providing specific support or ring-fenced funding to Local Authorities for Japanese Knotweed control. Local Authorities decide their priorities for widespread invasive species management locally.

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