Invasion by emerald ash borer (EAB; Agrilus planipennis Fairmaire), an exotic pest, is disrupting natural processes and hindering our ability to conserve genetic diversity and perpetuate ash ecosystem services and functions. The goal of this project was to identify ash-dominated community types that are most at risk in terms of having altered ecosystems following EAB invasion. Using recent data available from the U.S. Department of Agriculture, Forest Service, Forest Inventory and Analysis program (FIA), we calculated Shannon-Wiener species diversity index values for forest containing each of the six native ash species found in the eastern United States.
Results/Conclusions
These forest communities differed in their species diversity index values, and diversity indices varied across states for forests containing an individual ash species. In addition, communities containing ashes that are restricted in their range due to exacting microsite requirements consistently had lower diversity index values as compared to communities of ash species with greater geographical ranges. Finally, forest stand cohorts (i.e., seedlings, saplings, and canopy trees) had similar species diversity indices across individual ash communities. The stand-level species diversity index values quantified for individual ash species will provide managers with additional information for prioritizing EAB control measures and restoration efforts following EAB invasions.