New study assesses the environmental cost of managing Japanese knotweed

New research from Swansea University has looked at the long-term environmental impact of different methods of controlling Japanese knotweed.
The invasive species has been calculated to cost over £165million to manage every year in the UK alone. Its presence can hurt household real estate purchases across the country.
This has led to the development of different ways of trying to control it, but with sustainability becoming more and more important it is essential to understand the effect of these management methods.
A new study, led by bioscience professor Dr Sophie Hocking and looking at the whole life cycle and long-term impacts of different management approaches, has just been published in the online journal Scientific Reports.
Dr Hocking said: “In light of the current climate emergency and biodiversity crisis, the management and sustainability of invasive species has never been more important.
“The two are intrinsically linked – we know that invasive species can have substantial negative ecological, social and economic impacts, and the way we manage these species should mitigate this in a sustainable way to ensure that we do no more harm than good. .
“While there has been more research on how best to manage the plant, little is known about the sustainability of these approaches.”
This study follows previous research that has placed Swansea University at the forefront of expertise and understanding of Japanese knotweed.
In 2012, Professor Dan Eastwood and Dr Dan Jones launched the world’s largest knotweed control field trial, which tested key physical, chemical and integrated methods of controlling the species. The research was undertaken in close collaboration with Ian Graham, managing director of Complete Weed Control, and Advanced Invasives, a spin-off company run by Dr Jones.
This field study provided valuable information for Dr. Hocking’s work. Using a life cycle analysis (LCA) – a methodology for assessing the environmental impacts associated with all stages of the life cycle of a business process – to learn the relative environmental impacts of a range of management methods chemical and physicochemical properties of knotweed.
The researchers went beyond a focus on the use and end of life of these methods and assessed the environmental impacts of different management methods, including the production of materials and herbicides needed to control knotweed. ; something that is often overlooked when we evaluate durability. For the study, the team selected commonly used methods for knotweed management and used real data on time consumption, amount of materials used, and economic costs to assess their relative environmental impacts.
Of the methods tested, they found that the simplest approach – glyphosate-based foliar spray control methods – used the fewest materials, had the lowest environmental impacts, lowest economic costs, and is, therefore, the most sustainable approach to controlling knotweed. . The results are important for those who work with or are affected by the presence of Japanese knotweed on their land.
Dr Hocking added: “Currently there is a big conversation around the sustainability of herbicides and their ecological and human health impacts. Social perceptions of how we deal with invasive plants are really important, but we need our understanding of sustainability to be ingrained. in the empirical evidence.
“We hope this research will contribute to our broader understanding of the sustainability of different invasive plant management approaches and help inform current knotweed management practices.”