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Japanese Knotweed

Volume 776: debated on Monday 7 November 2016


Asked by

To ask Her Majesty’s Government what progress they have made in controlling the spread of Japanese knotweed.

My Lords, we continue to explore bio-control options through the controlled release of the psyllid insect Aphalara itadori. Releases have been carried out at 18 sites this year using improved methods to increase the chances of establishment. Local action groups, some established with Defra support, continue to reduce or eradicate Japanese knotweed in several places in England. Community protection notices are starting to be used by local authorities to address the nuisance this plant causes.

I thank my noble friend for that reply. Is he aware that I first asked this Question nearly 30 years ago? There has not been a great deal of progress. Is he aware of the man who killed his wife and committed suicide as he could not sell his property because of knotweed? Also, many people cannot get mortgages on their houses because of knotweed.

My Lords, first, I acknowledge my noble friend’s tenacity in seeking to deal with this brute of a plant. On mortgages, the Royal Institution of Chartered Surveyors published an information paper only last year that aims to help valuers and mortgage lenders better understand the implications of this plant for residential properties. We anticipate that this will lead to a more pragmatic approach between all parties in dealing with it. On what my noble friend said about the tragedy, this invasive species of plant is of great concern and we need to deal with it where we can.

My Lords, while the Minister’s work with the psyllid, the jumping plant louse, gets going, will he encourage local action groups around the country to tackle this dreadful plant in the ways it can already be tackled—though that needs a lot of work? Is he aware of the good work being done in my own borough of Pendle by an organisation called the Environmental Action Group? It employs young people who might otherwise have difficulty getting jobs, trains them and does good local environmental work. Along with the Ribble Rivers Trust, it has set about the task of eliminating Japanese knotweed from our borough.

My Lords, I certainly acknowledge what is happening in the noble Lord’s part of the world and I am well aware of the group in Pendle. Many local action groups are working to treat this problem and there is very good national coverage. As examples of where, with tenacity, we can deal with this, the Norfolk local action group eradicated all Japanese knotweed on the River Wensum special area of conservation, while in Bristol Japanese knotweed on all publicly owned land is now 95% under management. There are a number of good stories to tell. My view is that wherever people are determined to deal with this, it can be dealt with.

My Lords, the Minister recently wrote to me confirming that Defra has a list of non-native species on its national eradication programme but that Japanese knotweed is not on it. Is that not evidence that the Government have rather given up on trying to eradicate it from our shores?

My Lords, I must be clear: this plant has been in the country since the 19th century and is very widespread—unfortunately, we sent it from Kew up to Edinburgh, thinking it was interesting. The prospect of eradicating every bit of Japanese knotweed is, alas, not viable at the moment but we hope the psyllid will, if successful, weaken the plant. That is the whole purpose of it. Certainly, where we have had species such as the Asian hornet, we acted immediately to deal with it. There are a number of species on the list that we want to eradicate immediately but I am afraid that a plant such as Japanese knotweed has been here rather too long.

I thought one of the Bishops might have come in on this Question to help us. However, since we have experts such as the noble Baroness, Lady Sharples, and the noble Lord, Lord Greaves, in the House, have the Government thought of appointing one of them as a knotweed tsar to get rid of all this?

My noble friend would make an excellent tsarina. The noble Lord will be pleased to hear that we constantly update officials in the Scottish Government because, as I say, this occurs across our nation. We need to deal with it, which is why where local action groups work together, they have been successful. They use herbicides, injections, glyphosate and all sorts of things, and they are making a difference where they want to.

We could do what Dame Roddick did; when she went to Nepal and noticed that all the cyclamen were stopping water from flowing, she bought them and turned them into paper. If we could find a use for knotweed, all the Boy Scouts in the world could rush around to get it, raising money for our local charities.

I am all for raising money for local charities but, ideally, I would much prefer to have our native species than this invasive species, which is harming our natural environment.

Is the Minister aware that our noble friend Lady Sharples is somewhat of a patron saint among gardeners for her sustained attack on Japanese knotweed and for telling Ministers to get knotted every so often when they give excuses?

I know that my noble friend is tenacious and persistent. I very much hope she will continue to keep Defra and me on our guard, making sure that we do all the things, such as the Check, Clean, Dry and Be Plant Wise campaigns, that we need to make ourselves ever more biosecure.