What is the attitude of French managers towards invasive species when managing linear transport infrastructures?

International audienceLinear transport infrastructures (roads, rails, waterways) are known to be a vector of spread of invasive species. Japanese knotweed s.l. is in France one of the most worrying biological invasion and raises questions about the modalities of actions that must be implemented on such specific areas. There is today no unequivocal answer to this question. We observe a diversity of perceptions and practices that is partly linked to the uncertainties about the management of this plant. There is a need of knowledge relating to these perceptions and practices towards Japanese knotweed s.l. along the linear transport infrastructures, as well as the reasons that lead to this diversity of attitudes.We conducted an online photo-questionnaire survey of French managers whose mission relates to different kind of infrastructures: motorways (several concession companies), national roads (DIR), rails (RFF) and waterways (VNF). The questions dealt with their perceptions and practices towards the plant and with their profession (area of intervention, mission, training …).This survey enabled us to produce a map of the perceptions and practices at national scale. We expect a diversity of attitudes according to the type of surveyed stakeholders and their geographical area of intervention. These hypotheses, if confirmed, would mean that the management choices rely on individual and collective values and that the future shape of environmental action should be discussed and arbitrated between all stakeholders