D3410: Monitoring the impact of introduced emerald ash borer parasitoids: Factors affecting Oobius agrili dispersal and parasitization of sentinel host eggs

Emerald ash borer (EAB) Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive, wood-boring pest of North American ash trees (Fraxinus spp.). Biological control is thought to be one of the most promising management options available to reduce A. planipennis spread and impact. This presentation describes efforts to characterize the dispersal of introduced EAB egg parasitoids, as well as improve sampling methods. The study examined Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) dispersal distance and subsequent parasitism of sentinel EAB eggs shortly after release, as well as the impact of tree species where the host eggs were deployed. Sentinel EAB eggs were deployed on pairs of green ash (Fraxinus pensylvanica) and white fringe (Chionanthus virginicus) trees in circles around the release point up to 45 m away. While distance and tree species did not affect parasitism, significantly more EAB eggs were parasitized when deployed for 120 rather than 48 hours. Future studies using sentinel hosts may yield further insights into the spread and impact of EAB parasitoids over time.