Japanese Knotweed Alliance

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In 2001, a consortium of partners formed a Japanese knotweed project management board, the Japanese Knotweed Alliance.  The aim of the board was to oversee a scientific research programme which examined the potential for biological or natural control of Japanese knotweed in Great Britain.

The research was carried out by CABI and funded by the consortium of partners. The following organizations were represented on the board:

British Waterways; Cornwall County Council; Defra; Welsh Development Agency; Environment Agency; Network Rail; and South West of England Regional Development Agency.

Research funded by the Japanese Knotweed Alliance

Since those early days, and with further support from the USDA Forestry Service and British Columbia, CABI considered over 200 possible control agents. The research demonstrated that a sap-sucking psyllid โ€“ Aphalara itadori โ€“ from the plantโ€™s native range in Japan, is highly specific to Japanese knotweed and showed good potential for its control in Great Britain. 

Research demonstrated that the introduction of the psyllid would not adversely affect native biodiversity and could result in a significant reduction in costs associated with tackling Japanese knotweed conventionally through the use of chemicals and physical removal.

Research into biocontrol of Japanese knotweed is ongoing by CABI with continued support from some of the original partners, in particular Defra as well as a wide variety of smaller donors and partners.  The research is now advised by an Advisory Group which also includes botany and biocontrol advisors.

Learn more about the project in full.

Further information

If you are interested in reading more about the work carried out during this partnership, an interactive pdf has been created to archive webpages from the decommissioned Japanese Knotweed Alliance website (https://www.cabi.org/japaneseknotweedalliance/). Please note, as this is a legacy document, external links provided may either be broken, or appear dated.