Emergency Control Strategies for Hylurgops longipillus R. (Coleoptera, Scolytinae) Outbreaks: From Chemical Communication to Integrated Management

Simple SummaryA bark beetle namedHylurgops longipillusdamages Korean pine plantations in Northeast China, killing trees in scattered patches. To fight these outbreaks, we created an emergency control system based on the beetle’s attraction to tree odors. We observed that the beetles prefer pines with slightly yellow needles and that infestations expand outward from hotspots. Using the natural scents of pine, we developed a powerful attractant that captured an average of 69.4 beetles per set of five traps over five days (1.8 times the standard lure), and a repellent that reduced trap catches by 83.3%. We then combined the removal and safe disposal of infested trees, chemical sealing of stumps, the joint use of the attractant and repellent (a push–pull strategy), and tree vigor enhancement for emergency control ofH. longipillus. After three years of monitoring, beetle trap catches dropped by about 94%, and no new outbreaks occurred.Under climate warming, bark beetle outbreaks increasingly threaten forest health.Hylurgops longipillus, a native bark beetle in Northeast China, causes patchy mortality inPinus koraiensisplantations. We developed an integrated emergency control system based on host selection chemical ecology. Damage characterization revealed that adults concentrated on trees with 10–50% crown needle yellowing, and infestations expanded as discrete patches radiating from multiple epicenters. Electrophysiological and behavioral assays of host volatiles and some of their isomers yielded a highly effective attractant (69.4 adults per five-trap set over 5 d, 1.8× control) and a repellent reducing ethanol-baited trap catches by 83.3%. Emergency control techniques consisted of integrated management combining removal and safe disposal of infested trees, chemical stump sealing, push–pull trapping, and tree vigor enhancement. Three-year monitoring showed ~94% decline in trap catches, no subsequent outbreaks, and stable control. This attractant-centered, chemical ecology-based system can rapidly suppressH. longipillusoutbreaks and achieve long-term management, providing a scientific basis and operational framework for similar localized bark beetle emergencies under climate warming.