Japanese Knotweed

Lord Greaves Excerpts

Thursday 16th May 2019 Lords Chamber

Asked by

[Lord Greaves]

To ask Her Majesty’s Government what recent steps they have taken to eradicate Japanese knotweed.

[The Parliamentary Under-Secretary of State, Department for Environment, Food and Rural Affairs (Lord Gardiner of Kimble) (Con)]

My Lords, we are trialling biocontrol methods to control Japanese knotweed. The Centre for Agriculture and Bioscience International is working to establish the highly specific psyllid, Aphalara itadori, into the United Kingdom. This summer, a population of a more climatically suitable psyllid from Japan will be brought here. It is hoped that 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.

[Lord Greaves (LD)]

My Lords, it is 30 years since Lady Sharples started asking questions about Japanese knotweed, and about 12 or 15 since I joined her, but all we get is the same answer every time: that this wonderful psyllid, Aphalara, will come galloping over the horizon and solve everything. It is absolutely clear that the problem of Japanese knotweed is getting worse and worse and causing more and more problems, and it is simply not being tackled. Do the Government agree that two things need doing? First, owners of land need to be put under a legal obligation to eradicate Japanese knotweed, and allowing it to grow should be an offence. Secondly, when transactions or contracts are made relating to land that has Japanese knotweed on it, or when people walk on it and may spread it, they should be notified that this dreadful, awful weed exists or has recently existed on that land.

[Lord Gardiner of Kimble]

My Lords, trials often take longer than we wish, but I assure the noble Lord that we are collaborating with Canada, because it has a similar problem, and with experts across Europe and the United States. I agree: it is frustrating that the psyllid has not established as we wished. We are working on another form of control, which is also under evaluation: a mycoherbicide. This is all part of using the science. I agree with the noble Lord that it is very invasive. That is why I will read some of the advice in the Science and Technology Committee report that came out this morning. We need to attend to this. The problem with the noble Lord’s first point is that, if someone fly-tips spoil with elements of Japanese knotweed, will the landowner really be required to remove that fly-tip? That is the problem if you make it a legal liability on the landowner to remove it.