Abstract Survival of North American species ash (Oleaceae: Fraxinus spp. L.) is threatened by emerald borer (EAB), Agrilus planipennis (Fairmaire), a phloem-feeding beetle that destroys the vascular system its host. In forested sites where dominant overstory species, mortality caused EAB can substantially alter conditions, with potentially cascading effects on ecosystems. urban forests, trees w...