Control of Emerald Ash Borer with Systemic Insecticides
The emerald ash borer (EAB) is the most destructive forest insect ever to have invaded North America. Since its discovery in 2002, it has killed hundreds of millions of ash trees in urban and natural forests and threatens the entire ash resource. Systemic insecticides are increasingly used to control pests in landscape trees because they are typically injected into the trunk or applied to the bark or soil, avoiding problems with aerial sprays such as drift, applicator exposure, and non-target effects. Forest Service scientists evaluated several systemic insecticides for control of EAB adults and larvae, and determined the translocation pattern of one insecticide within ash trees. All of the systemic insecticide products tested were toxic to EAB adults and reduced larval densities in trees for one or two seasons post-treatment. Systemic insecticides were also toxic to EAB larvae fed artificial diet treated with various doses. Levels of adult mortality, reductions in larval density, persistence, and lethal concentrations varied among insecticide treatments. They found that ash trees have sectored flow that could lead to uneven distribution of insecticide in tree crowns and could partially explain variability in control of EAB. Systemic insecticides provide viable options to protect landscape trees from EAB.
Forest Service Partners