SMARTIES: Surveillance and Management of multiple Risks to Treescapes: Integrating Epidemiology and Stakeholder behaviour

Tree-species in the UK are threatened by an increasing number of pests and diseases resulting in large economic, environmental and social costs. Preventing the introduction of such threats is often difficult, therefore, early detection and successful management are key areas where science can deliver. There are over 1000 threats on the UK plant-health risk register, and many are serious pests of tree species. A tree-host may therefore face more than one threat at once. There have been previous calls for more systems approaches to managing biosecurity threats but scientific research still tends to focus on single species, ignoring possible interactions of multiple pests/ diseases and the fact that land managers focus on managing the tree, rather than managing a pest or disease. A second facet that is often neglected by science-based approaches is the ability and willingness of managers to adopt advice on the surveillance and management of pests and diseases as well as the acceptability of different approaches in wider society. In this project, we will develop a truly interdisciplinary approach to understand the key epidemiological and human behavioural factors that govern the invasion and spread of multiple threats to tree health and so determine successful surveillance and management at a whole system level, rather than on a pest specific basis.

Emerging threats to UK ash trees (Fraxinus excelsior) offer an important case study for our research. This UK native tree species is currently impacted by Ash Dieback (ADB), a devastating disease which is reported to have caused an estimated loss of £15 billion to the UK economy. However, ash trees in the UK face a new threat from the potential invasion of the Emerald Ash Borer (EAB), Agrilus planipennis. Although not here yet, EAB is ranked in the top three most dangerous invasive pests by EFSA. Its presence has been confirmed in Russia and it is moving West. Surveillance for EAB in the context of the already well established ADB is likely to be much more challenging because of the uncertainties surrounding ADB and EAB interactions, Ash trees that may be impacted by both ADB and EAB will further complicate management decisions faced by landowners and policy makers.

Our partnership comprises expertise in (i) modelling epidemiological processes, (ii) the design of surveillance strategies, (iii) plant pathology and entomology, (iv) the human dimensions of tree pests and diseases (v) modelling of human behaviour and forest management decision-making. We bring together the ideal combination of skills to tackle the challenge of managing new and emerging pest threats. Drawing on our experience, we will develop a model of the distribution and spread of ADB and the dispersal of EAB in a spatially explicit landscape. By analysing data on the spread of EAB from the USA and Russia we will determine the effect of both natural and anthropogenic spread that can occur. This will be used to inform and validate our epidemiological model. We will integrate this model with a novel model of stakeholder behaviour based on our social science research that captures the important attitudes and behaviours that affect decisions related to surveillance and control. Stakeholder perspectives and decision-making will be modelled dynamically allowing them to realistically change over time in response to peer and external influence. The linked models will allow us to identify how best to deploy surveillance and management resource to account for the impact of environmental conditions on risk and the sociological factors that influence biosecurity knowledge, attitudes and behaviours and identify approaches to improve social acceptability of management actions. We will use our model-based analysis to co-design surveillance and management solutions with key stakeholders including Defra EAB preparedness board, EFSA, the Forestry Commission that will inform and feed into policy development.

Introductions of new tree-pests and diseases are increasing rapidly in the UK. The recent study of Ash dieback in Great Britain revealed its full economic cost to be £15 billion and the introduction of the pest the Emerald Ash Borer (EAB) would amplify this further and lead to the large-scale loss of ash from the British countryside Working closely with a range of stakeholders this project will deliver a set of biosecurity recommendations that acknowledge the need to manage multiple threats simultaneously, and which, crucially, are underpinned by an understanding of the interplay between both epidemiological and behavioural processes.

This project will be of benefit to:

(1) National and International Plant Health Agencies. The project team has long established relationships and advisory roles within national plant health agencies and inspectorates in the UK and internationally including Defra, Forestry Commission and the UK Plants and Seeds Inspectorate (PHSI), European Commission DG Sante and European Food Safety Authority (EFSA). This will enable co-design and co-delivery throughout the project. Through our links with Defra, we will present our work at the annual APHA plant health inspectors' conference, as well as the annual APHA modelling symposium which is attended by a broad range of policy makers. Defra support the project and have been involved in the proposal development. We will engage with Defra Plant health policy through frequent ad-hoc meetings throughout the project, as well as formal annual workshops and biannual updates to the wider stakeholder group. Members of the proposal team provide regular advice to international plant health bodies. For example, surveillance advice to the European Commission and EU through membership of the EFSA Plant Health Panel, participation in the EU Scientific Network and expertise on the social dimension of tree health to the IUFRO Working Party.

(2) Horticultural trade, Land owners and managers. We are already engaged with stakeholder groups, such as the Horticultural Trades Association, in our current and ongoing projects and will ensure KE through formal and informal channels. We will provide materials to interest groups to include in their publications and present at events they organise.

(3) Members of the public. To maximise impact, results will be delivered through a ongoing dedicated project website (hosted by Rothamsted) and social media strategy. The latter will primarily be achieved through a dedicated twitter account. All research organisations (ROs) involved in the project have a long-standing public engagement activity agenda, and actively participate in Science communication events such as the annual National Science and Engineering week. We will use these types of opportunity to showcase the proposed project and so raise awareness of the issues. Rothamsted also holds public meetings 4-5 times a year to discuss contemporary scientific matters. All ROs have professional in house media teams and have experience working with national and international media, particularly on communicating trees pests and diseases. This will be further exploited to communicate and engage the public which can be very effective. The members of the proposal team are involved in the UKRI Xylella project, BRIGIT, which received over 11,000 public reports of the Xylella vector following a BBC news article.