Optimizing early detection strategies: defining the effective attraction radius of attractants for emerald ash borer Agrilus planipennis Fairmaire

Abstract

Abstract Adult emerald ash borers are attracted to green prism traps baited with the ash host volatile (3Z)‐hexenol and the sex pheromone of emerald ash borer (3Z)‐dodecen‐12‐olide [(3Z)‐lactone]. Quantifying the heretofore unknown range of attraction of such traps would help optimize deployment strategies for early detection. Examining trap captures of traps deployed in pairs at variable distances offers insight into the range of attraction. Recent work has shown the range of attraction can be estimated as half the intertrap distance at which trap catch begins to decrease, which should occur when proximate traps overlap their respective attractive ranges. We estimated these traps' attractive range for emerald ash borer using 98 baited dark green prism traps deployed in pairs, one trap per tree, in an urban park in Saint Paul, Minnesota, USA in summer 2020. We estimate attractive range by fitting a logistic model to trap catch data using Bayesian inferential methods and describe advantages thereof. The attractive range of these baited traps was estimated to be between 16 and 73 m, with a median of 28 m. We recommend that dark green prism traps baited with these semiochemicals be placed 25–35 m apart near high‐risk entry points.