When the Bough Breaks: How Do Local Authorities in the UK Assess Risk and Prepare a Response to Ash Dieback?

Ash dieback Hymenoscyphus fraxineus (T. Kowalski), is an alien fungal disease probably introduced to Europe from Asia that currently presents a significant threat to native ash (Fraxinus L. spp.). In the United Kingdom a large proportion of ash trees are found outside of woodlands. This means that a wide diversity of land owners and managers are stakeholders in the response to ash dieback. Local authorities (local government units) hold responsibility for managing ash trees along the highways and other public sites, with a focus on maintaining public health and safety. Developing local action plans (LAPs) for ash dieback is promoted by the government as way for local authorities to plan an effective strategic response at a landscape scale. However, risk assessment frameworks and the knowledge about ash dieback that is needed for quality decision-making at this level is still lacking. The scientific uncertainty around ash dieback progression, mortality rates, and the hazards presented by the trees at different stages of infection present knowledge problems. The research aims to (i) develop and evaluate an approach to addressing ash dieback suited to local authorities across the United Kingdom, and (ii) address the research gaps surrounding the local authority approaches to risk assessment and overcoming "knowledge problems." Our hypothesis is that action research can be used to develop an effective risk assessment framework and knowledge tools that can improve decision-making. Our research questions in support of these objectives are: (i) How do local authorities perceive, assess, and plan for risks? (ii) What information and knowledge do local authorities need to assess and manage the specific risks of ash dieback? Lastly, (iii) what processes drive the local authorities toward preparing and implementing LAPs? Data collection occurred between 2015–2019 and included: deliberative co-production and validation workshops, two survey questionnaires, and evaluative semi-structured interviews (SSIs). Local authorities were shown to assess risk and proportionality of response to ash dieback through processes of deliberative social learning mixing opinion, scientific and practice-based knowledge to reach a consensus over the methods and knowledge that would be used in decision-making. Placing ash dieback on corporate risk registers that cut across the multiple departments dealing with the problem facilitated political approval, action planning, and budget allocation. Generating locally specific knowledge and finding the resources and personnel to drive forward strategic planning and implementation were key to landscape scale responses and ratifying LAPs. Collaborative action research working on ways of assessing, learning, and responding to tree pests and diseases offer an important approach to problem-solving and developing responses at the landscape scale. [ABSTRACT FROM AUTHOR]