Understanding public perceptions of tree health risks: an actor-network approach

Outbreaks of new invasive tree pests and diseases have increased over recent years, some of which present a significant risk to tree health, plant biosecurity and ecosystem functions. These outbreaks often involve complex and sometimes contradictory interactions between attempts by governments to manage them, media coverage and the diverse risk perceptions of stakeholders and publics. In this paper we draw on insights from actor-network-theory to guide our methodological approach to understanding expert and public risk concerns around three tree pest and disease outbreaks in the UK: ash dieback, oak processionary moth and Phytophthora ramorum. We argue that the 'risk' of tree pests and diseases does not exist in an objective sense that can be measured, but is constantly being produced (and reproduced) through the associations between people and nonhumans in actor-networks. Thus, tree pest and disease outbreaks can be conceptualized as part of assemblages of actors (publics, policy makers, biological organisms etc.), enactments (policy, regulation, performance etc.) and materialities (places). We draw on work currently being undertaken as part of the UK's Tree Health and Plant Biosecurity Initiative Phase 2 project UNPICK (Understanding public risk in relation to tree health) which includes exploring the personal and professional encounters that people have with pests and diseases in particular locales. We focus on the intersections and translations that occur through those encounters to understand how problems like tree diseases are constituted, risks understood and management approaches assembled.