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Japanese Knotweed

Volume 785: debated on Tuesday 7 November 2017


Tabled by

My Lords, on behalf of my noble friend Lady Sharples, and at her request, I beg leave to ask the Question standing in her name on the Order Paper.

My Lords, this aggressive plant was first found in the wild in the United Kingdom in 1886 and has unfortunately become widespread here and across Europe. We are working to ensure a more successful establishment of a psyllid insect to control it. Meanwhile, local action groups, with support from government, continue to reduce and eradicate the plant; for instance, in the Medway Valley and the New Forest, where 49 separate sites have been tackled this year.

Is my noble friend aware that when knotweed stems are trimmed they are eaten by Japanese children? Will he tell us whether landowners with knotweed on their property can still obtain a mortgage?

We are discussing an invasive species. Although I am well aware that in Japan young shoots are consumed, I would not advise it here. I do not think that is a very sensible proposal for this county. On mortgages, some new policies are now available and the RICS put out a very helpful paper in 2012, which has assisted in this matter as well.

Is my noble friend aware that by far the most effective technique for controlling Japanese knotweed is the use of the broad-spectrum herbicide glyphosate, otherwise known as Roundup, which is under threat of being banned, even though it is entirely safe according to most international agencies, with the exception of one debunked study by a scientist who, it now appears, was in the pay of bounty-hunting US lawyers? Will the Government stand firm on the relicensing of glyphosate?

My Lords, the Government are absolutely clear that we should consider these matters on the best scientific assessment available. Both the European experts and our own experts think that glyphosate should be approved. The important point about its use on Japanese knotweed is to spray the underside of the leaves as well.

My Lords, I pay tribute yet again to the noble Baroness, Lady Sharples, for her persistence in this matter. I am very sorry she cannot be here today and, if she is poorly, I hope she gets better as quickly as possible. The Minister referred to a two-pronged approach but over the years the Government have put too much hope on the prospect of armies of jumping psyllids crossing the land, chewing the knotweed in their path and getting rid of it. That will not be the answer, not for a long time at least. Is not the answer in the short run the work of local action groups, local authorities and others, to which the Minister referred? Is it not the case that the Government ought to be giving a lot more strong advice to local authorities to get on with it, because this stuff can and ought to be removed?

There are good examples of where local action groups have worked effectively and eradicated Japanese knotweed. In Defra we have an official who is co-ordinating the work of the local action groups. I very much endorse their work and think it is the way forward. However, research shows that we should be looking for a more robust psyllid. We have released in 16 sites this year 120,000 psyllids and I hope we will see some progress in that regard.

My Lords, there is another very invasive species called the US crayfish, which destroys riverbanks and fish and other life in the river. Like knotweed—I got there—it can be consumed. Unfortunately, however, the licence to do so is only partial across the south and part of the Midlands; in the north of England, Scotland and Wales they simply have to be destroyed. Will the Minister consider, alongside the measures on knotweed, ensuring that we can get a grip on the US crayfish problem?

My Lords, I am well aware of what the noble Lord said about crayfish—this is why they are non-native invasive species—and of the importance of seeking to manage and, wherever we can control and eradicate them. They are very bad news for our watercourses. I will look into the problem, but it is very much a matter for Natural England.

My Lords, is my noble friend aware that, although a duty is laid on councils and local authorities under the noxious Weeds Act to control other noxious weeds, not least ragwort, which is poisonous to horses, one can drive along the roads and motorways of this country and see ragwort growing at the sides? Councils do not comply with their duty under the law. When will something be done about that?

My Lords, as we all know, ragwort is extremely toxic to animals and it is important that authorities and everyone should understand the issue of controlling it. Unfortunately, it is very widespread and I very much hope that authorities will adhere to dealing with ragwort.

My Lords, I rise with some trepidation on this subject given that there are so many experts in your Lordships’ House, but I came across Japanese knotweed recently in a private burial ground in the London Borough of Enfield. I declare an interest because it is where members of my family are buried. I have written to Enfield Council asking what it will do about it, because it is growing wild and destroying graves. I have been told that it is not the council’s responsibility because it is private land. Will the Minister clarify whose responsibility it is? Is it the local authority’s when it is within the boundaries of the borough or the private landowner’s? What powers does the local authority have to issue enforcement on this?

My Lords, there are community protection notices, which give local authorities and the police powers. I suggest that the noble Baroness considers that way forward.

My Lords, is the Minister aware of Japanese seaweed? I do not think you can eat it, but it is a serious invasive species in our watercourses and rivers. What action will the Government take to try to control that?

My Lords, there is a list of invasive species that we very much want to manage and control. The most important thing is biosecurity and awareness campaigns such as “Check, Clean, Dry”. We each have a responsibility to help deal with invasive species.