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About us

In 2001 a consortium of partners were brought together to form a project management board. 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 is carried out by CABI and funded by a consortium of partners:


CABI is a science-based not-for-profit organization that specialises in agricultural and environmental research. Its mission and direction is influenced by its 45 member countries who help guide the organisation's activities. These include scientific publishing, projects and consultancy, information for development and mycological services.

CABI was contracted to undertake research on behalf of the project board. CABI scientists have been conducting research into potential natural control agents to combat Japanese knotweed since 2000. This work entailed the collection, identification and selection of Japanese knotweed's natural enemies. Potential agents were assessed in a Defra-licensed quarantine facility and all work was carried out according to international protocols.


The Department for Environment, Food and Rural Affairs role is to help enable people to live within their environmental means. Defra's priority is to ensure that the resources we need and environment we enjoy continue to be available for us all, now and in the future.

Defra holds policy responsibility for non-native species and plant health. It is working with the Central Science Laboratory (the licensing authority) to ensure that a scientifically rigorous licensing process is followed before any release of a natural control agent for Japanese knotweed.

Environment Agency

The Environment Agency is the leading public body for protecting and improving the environment in England and Wales. Its job is to make sure that air, land and water are looked after by everyone in today's society, so that tomorrow's generations inherit a cleaner, healthier world.

The Environment Agency is committed to improving the ecological quality of our water environment. It is also responsible for managing flood risk. River corridors dominated by a dense monoculture of Japanese knotweed damage biodiversity and reduce the capacity of the watercourse to cope with floodwater. It also reduces the amenity value of the river and its aesthetic value to the local community. Currently, herbicides are used to manage Japanese knotweed. The Environment Agency seeks a safe, specific and sustainable alternative that will pose no risk to water quality or the wider environment.

Welsh Assembly Government

The Welsh Assembly Government aims to ensure the development of 21st century Wales as a self-confident, prosperous nation, committed to social justice and sustainability. Accountable to the National Assembly for Wales, it offers a progressive agenda for improving quality of life for all communities, including measures to support the Welsh language.

The former Welsh Development Agency (WDA), now part of the Welsh Assembly Government's Department for the Economy and Transport, provided funding to conduct research into a natural control for Japanese knotweed. The WDA was one of the founding members of the research programme and the alliance. Funding for some of the preliminary research phases which has led to the current successful phase of work also came from Wales. Japanese knotweed has a huge economic cost to development and regeneration in addition to the impacts on biodiversity and landscape. The costs of eradicating Japanese knotweed from a site due to be developed can be extremely significant, particularly South Wales which is one of the worst affected areas in the UK. The Welsh Assembly has worked in partnership with a variety of other UK-wide funding bodies to support this research by CABI into the natural control of Japanese knotweed.

South West Regional Development Agency

The South West Regional Development Agency leads the development of a sustainable economy in South West England. The Agency’s core strategy is focused on creating the conditions for productivity-led growth.

Network Rail

Network Rail is the 'not for dividend' owner and operator of Britain's railway infrastructure, which includes the tracks, signals, tunnels, bridges, viaducts, level crossings and stations - the largest of which we also manage. Their aim is to provide a safe, reliable and efficient rail infrastructure for freight and passenger trains to use.

Network Rail is working hard to create a lineside environment in order to run a safe and reliable railway, incorporating open space, grassland, low-growing shrubs and trees. Japanese knotweed undermines Network Rail's efforts owing to its fast, voracious growth rate, and it can cause damage to buildings and embankments while out-competing native species. Successfully controlling Japanese knotweed takes up valuable resources in terms of time and money – resources that could be better spent elsewhere on maintaining and improving the railway.

Cornwall Council

Cornwall Council is Cornwall’s largest democratic organisation and is focused on providing a strong and sustainable community for one and all. It aims to do this by improving individual development and well being, fostering the success of all communities, enhancing the living environment, promoting Cornwall to the world, being a strategic, ambitious, accountable and well-managed Council, providing leadership and delivering services.

Cornwall Council, on behalf of the Natural Control of Japanese Knotweed Board, is responsible for the co-ordination of the project. It is hoped that this research will identify another control method to complement and, in some cases, replace existing treatments.

Canal & River Trust

The Canal & River Trust (formerly British Waterways) cares for 2,200 miles of historic canals and navigable rivers, working to ensure that the 200-year old network continues to benefit the nation now and into the future. It works with a broad range of public, private and voluntary sector partners to unlock the potential of the inland waterways and generate income for reinvestment in the network for the benefit of the millions who visit the waterways every year.

CABI logo Cornwall Council logo DEFRA logo environment agency logo Network Rail logo SWRDA logo Welsh Assembly Government logo Canal and River Trust