Interspecific Competition Between Idiobiont Larval Parasitoids of Emerald Ash Borer

New associations between parasitoid species is common in biological control with interactions ranging from coexistence to competitive exclusion. Spathius agrili and galinae, native North East Asia, are two host-specific idiobiont larval parasitoids of the invasive emerald ash borer Agrilus planipennis that do not overlap their ranges but have been recently introduced United States for biocontrol A. planipennis. We conducted laboratory experiments determine results competition these species. Competition larvae on a single host (intrinsic competition) adult oviposition sites (extrinsic were evaluated. Successful multiparasitism did occur any intrinsic trials. Extrinsic favored S. agrili, galinae was excluded. lowered parasitism rates both species, overall lowered.