Wednesday 9 April 2014

knotweed speech

To my constituents, the term ‘non-native invasive species’ means only one thing: Japanese knotweed, or, as it is known locally, Sally rhubarb, due to a similarity in shape and colour to rhubarb, though unfortunately not in height. I heard the Minister at the weekend describe how, when he was growing up in Tredegar, he thought all rivers were multi-coloured; when I grew up in Plasmarl in the Swansea East constituency, I thought that everywhere was covered in knotweed.


Senedd.tv


   
 
Japanese knotweed is a plant native to Japan, Taiwan and northern China. It was first introduced to the UK in the early 1800s as an ornamental plant, unfortunately. The plant can grow in excess of 3m in height and is commonly seen on river banks, alongside train lines and on waste ground. In Swansea, we have at least five train lines running through the constituency: the London main line, the Swansea to Fishguard line, the Port Talbot to Felindre and Trostre line, the Swansea Valley to the docks line and the LMS line. With the exception of the LMS line, all of these lines run along steep banks. Knotweed was used to protect the banks from collapse and to protect the railway line in its journey along the Valley floor. Unfortunately, it has not stayed there; due to a whole range of things happening, it has spread throughout the whole of the constituency.


   
 
Each year, public authorities in the UK spend about £1.6 billion in treating and removing Japanese knotweed. A recent estimate put the cost to the British economy at £165 million. In the UK, Japanese knotweed has no natural predators or controls. Consequently, it has been able to colonise areas throughout the country with, I believe, the exception of only the Orkney isles. The plant is extremely invasive and thrives on disturbance. The tiniest piece of stem can regrow, and can be spread both by natural means and by human activity—often on the soles of shoes, or attached to coats or jackets. It threatens the survival of native plant species and insects and native animal species.


   
 
Other problems include the accumulation of litter among the stems; riverside erosion when knotweed dies back; and damage to buildings, pavements and car parks. Knotweed is able to grow through both asphalt and concrete. Concreting over will not solve the problem.


   
 
There are few lenders who will finance the purchase of property if knotweed is present in the garden, in a neighbouring property or, more likely, in the area, often on land of unknown ownership. This is causing difficulty for those looking to sell and get a mortgage. The presence of knotweed devalues a property massively and causes huge problems to the people concerned.


   
 
Linking to yesterday’s debate on the housing Bill, there are now a number of reluctant landlords unable to sell their houses due to knotweed, often on adjoining land that has no known owner. They are unable to sell their property so they become landlords and rent out their property because it is the only thing that they can do with it.


   
 
There are two main types of treatment for knotweed: physical control and chemical methods. In July 2009 the Department for the Environment, Food and Rural Affairs announced a plan to release a native—I hope I get this right—psyllid bug aphalara itadori into the wild. It is a natural enemy of the knotweed. It is the first time that biocontrols have been used in the European Union to fight a weed. Initially it would be deployed at a limited number of test sites before wider release in England and Wales. The Centre for Agricultural Bioscience International is currently halfway through a study and has reported that the insect is coping well in the UK.


   
 
The sites, I understand, are meant to be secret, but there is a general belief locally that one of them is in Swansea East. Recent estimates put Swansea alone at having 62,000 tonnes of knotweed, equivalent to the weight of 400 blue whales. The overall infestation has been estimated to cost about £9.5 million in chemical treatment, and will take approximately 50 years to eradicate using conventional methods and current treatment rates, and that is without taking into consideration its spread to new areas. Over the past 10 years, Swansea council alone has spent over £200,000 on controlling knotweed.


   
 
I end with three questions to the Minister. If Natural Resources Wales becomes the lead organisation for addressing invasive, non-native species, does it mean that extra funding will be given to its annual budget to deal with this substantial knotweed problem? Will areas with a high concentration of knotweed, like Swansea, have additional support? Finally, although studies are ongoing, can the Welsh Government give any positive, meaningful news on combating knotweed using biologically controlled test sites in Wales using the Aphalara itadori insect native to Japan? In many respects, knotweed is one of the biggest issues in the whole of my constituency, dwarfing a range of other issues that people treat as the big issues of the day.


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