Evaluating semiochemical‐based strategies for managing ambrosia beetles in apple orchards

Abstract Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) have emerged as problematic pests in Michigan apple orchards, where their cryptic lifestyle complicates effective management. This study evaluated the efficacy of semiochemical‐based repellents in mitigating beetle infestations, focusing on two key invasive species: Xylosandrus germanus and Anisandrus maiche . Trials conducted in 2023 and 2024 assessed the repellency of verbenone, methyl salicylate, conophthorin and a wax‐based flowable repellent (BeetleGuard, a combination of verbenone and methyl salicylate) in both semi‐field and orchard settings. High‐density repellent applications significantly reduced new boring holes per tree in orchards, with efficacy dependent on repeated applications throughout the growing season. These findings highlight the potential of semiochemical repellents as part of an integrated management strategy for ambrosia beetles in orchards. Future research should refine application methods and evaluate environmental and behavioural factors influencing repellent efficacy to optimize protection for apple production.