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House of Lords written question HL774.

Question for Department for Environment, Food and Rural Affairs

UIN HL774, tabled on 23 January 2020

To ask Her Majesty's Government what progress they have made in eliminating Japanese knotweed.

Answered on

28 January 2020

The Government recognises the threats posed by invasive non-native species including Japanese knotweed and has a comprehensive Great Britain Non-native Species Strategy designed to tackle these threats, the first of its kind in Europe.

Local Action Groups, with support from the Government, are actively involved in reducing and eradicating Japanese knotweed. Increasing public awareness of the species and what can be done about it is an important part of tackling the problems caused by Japanese knotweed. To that aim, we launched the first Invasive Species Week in 2015, to bring together a wide range of organisations to raise awareness of invasive non-native species, to highlight work going on to tackle them and to inspire people to get involved and help prevent their spread. Invasive Species Week has gone from strength to strength, with eight administrations taking part in 2019 and 93 events held.

Defra continues to fund a biocontrol programme through the release of a psyllid insect to tackle Japanese knotweed. The Centre for Agriculture and Bioscience International (CABI) is working to establish the highly specific psyllid Aphalara itadori in the UK and a population of climatically suitable psyllids from Japan is being studied in CABI’s quarantine in Surrey. It is hoped this will be the key to unlocking the potential of this agent to reduce the effort and cost of managing Japanese knotweed and its invasive capacity. Research is also underway to evaluate a leaf-spot fungus for use as a mycoherbicide.

The Government has developed guidance on how to prevent the spread of Japanese knotweed, which can be found at:

https://www.gov.uk/guidance/prevent-japanese-knotweed-from-spreading