Risk, climate and host suitability layers for Phytophthora ramorum and Phytophthora kernoviae plant pathogens in Scotland

The spatial layers presented in this aggregate represent the linked climate, host and risk model outputs from research aiming to develop a spatial risk framework for Phytophthora ramorum and Phytophthora kernoviae. Novel pest and pathogen species are arriving at increasing rates through global trade and travel with high impacts on ecosystem and plant health. Over the past 13 years, five new species of pathogenic Phytophthora (Phytophthora ramorum, P. kernoviae, P. lateralis, P. austrocedri and P. pseudosyringae) have been detected in Britain, damaging forest ecosystems and affecting trade in timber and plant products. Following emergence, the impacts of these pathogens vary across the landscape depending on available plant hosts, suitable climatic conditions for infection, proximity to spread pathways and management factors. This research aimed to develop a spatial risk framework for Phytophthora ramorum and Phytophthora kernoviae to guide surveillance and control in Scotland, encompassing these key factors affecting establishment and spread. The spatial layers presented in these four datasets represent the linked climate, host and risk model outputs from this research. The project was funded by the Scottish Government under a project entitled 'Study of the epidemiology of Phytophthora ramorum and Phytophthora kernoviae in managed gardens and heathlands in Scotland' (research contract CR/2008/55 and extension CRF925_extension) and involved collaborators from St Andrews University, Science and Advice for Scottish Agriculture (SASA), Scottish Natural Heritage (SNH), Forestry Commission, the Food and Environment Research Agency (FERA) and the Centre for Ecology & Hydrology (CEH).

The climate layers map temporal variability in suitable climate conditions for pathogen infection, developed by linking empirical responses to temperature and relative humidity to hourly variability in these conditions across the country. The host layers arise from new environmentally driven habitat suitability models, parameterised using citizen science and survey data, for both known woodland reservoirs of infection like Rhododendron ponticum and susceptible heathland species like Vaccinium myrtillus. Spatial layers of relative risk scoring are presented for susceptible fragments of heathland, Core Native Woodland and known larch fragments across Scotland. Risk factors included climate suitability, proximity to road and river networks and suitability of habitat for key hosts of Phytophthora and were broadly concurrent with the period between 2007 and 2013.