EPPO Global Database

EPPO Reporting Service no. 10 - 2015 Num. article: 2015/196

How environmental managers perceive invasive species issues

Fallopia japonica, Fallopia sachalinensis and Fallopia x bohemica (Polygonaceae), hereafter referred to as Japanese knotweed collectively, are significant invasive alien plants within the EPPO region and thus included within the EPPO List of Invasive Alien Plants. Throughout the Rhône River catchment (FR), environmental managers are continually working to control invasive populations of Japanese knotweed using various management options, and increasingly a lot of effort is put into awareness raising to prevent further spread. As a result, detailed documents are produced in the form of management plans, information leaflets, publications and reports from technical meetings. When analyzed collectively, these documents can give insights into the perceptions of environmental managers to Japanese knotweed and how these vary depending on the type of environmental manager involved, the geographical area and the scale of the problem. In the present study, 81 documents published between 1998 and 2013 were collected from environmental managers from a wide spectrum of organizations – including regional water authorities, environmental consultancy firms and regional conservation bodies. The documents were analyzed both qualitatively and quantitatively. A higher number of documents were produced up-stream compared to the lower stretches of the river and this correlates with the upper stretches of the river being more invaded. Managers working within local water associations were the main stakeholders to disseminate information about Japanese knotweed, producing almost half of the documents analyzed. Those working at a regional level were more focused on providing general information whereas managers implementing actions locally were more inclined to produce documents detailing technical methods for controlling and eradicating Japanese knotweed. What was clear from the study was irrespective of who produced the documents, all agreed on one point – the need to take action against Japanese knotweed.


Cottet M, Piola F, Le Lay YF, Rouifed S & Rivière-Honegger (2015) How environmental managers perceive and approach the issue of invasive species: the case of Japanese knotweed s.l. (Rhône River, France). Biological Invasions. DOI: 10.1007/s10530 015–0969–1.