Project Number: 8010-22000-031-06-A
Project Type: Cooperative Agreement
Start Date: Sep 15, 2019
End Date: Sep 15, 2021
The proposed research aims to develop and test a biocontrol-based Emerald Ash Borer (EAB) management strategy that utilizes our understanding of the EAB invasion process, EAB population dynamics, and new control tools, including releases of the more recently approved larval parasitoid Spathius galinae and limited trunk injections of systemic insecticides. At research sites in Lower Michigan, where the EAB biocontrol agents were released (2007-2011) as the first EAB infestation wave peaked and most large overstory ash trees were dead or dying, we will focus on evaluating the impacts of EAB biocontrol agents on host population dynamics and on ash growth, regeneration, and conservation in the aftermath of EAB invasion. At research sites in the Northeastern U.S., where the biocontrol agents were released in conjunction with systemic insecticide treatments to control EAB in the large overstory ash trees, we will collect similar data, but include data on ash tree survival, growth, and reproduction before and/or during the outbreak phase of EAB invasion.
The proposed work will be carried out in both Lower Michigan and the Northeast region (CT/NY/MA). In both regions, data on ash inventory and demographics, EAB infestation rates, EAB mortality factors including parasitism by the introduced biocontrol agents, disease, host resistance, and abiotic factors will be collected and form the basis for developing an integrated EAB management program. The focus of EAB management strategies in Michigan will be on establishing and/or maintaining the low EAB density equilibrium so that existing ash can survive and grow to overstory trees, and ash sapling are regenerated in the aftermath of EAB invasion. Tactics to achieve this goal will include (1) additional releases of the newly introduced EAB parasitoid (S. galinae) across the region as well as previously introduced parasitoids (T. planipennisi and O. agrili) in non-established areas at relatively high temporal and spatial frequencies and (2) evaluating forested areas in Northeastern States (CT/MA/NY), where limited trunk injections of emamectin benzoate were applied in 2016 and EAB densities are still relatively low.