Efficacy of selected synthetic pesticides, biopesticides, and microbial agents against rednecked cane borer and raspberry crown borer

The rednecked cane borer, Agrilus ruficollis (F.) and raspberry crown borer, Pennisetia marginata (Harris) are pests of blackberries throughout the United States. Rednecked cane borer larva causes a gall in bramble primocanes predisposing canes to winter injury whereas raspberry crown borer larvae tunnel in crown and lower canes causing decline in plant yield and vigor. The current scouting methods are to either walk bramble plantings weekly in May and June to note presence of adult rednecked cane borers on primocanes or in September and October to inspect underside of leaves for brown raspberry crown borer eggs. Cultural practices include removal of galled primocanes (rednecked cane borer) or removal of larva in damaged canes or infested crowns (raspberry crown borer). Given more than a 10% pest infestation, growers use insecticides to control either pest, but have a limited choice of registered chemistries. The objective of this experiment was to test the efficacy of different synthetic, biopesticide, and microbial formulations against these two pests. Results from this experiment demonstrate that there are several other options for growers to use to successfully prevent damage from either pest.