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Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is an invasive pest causing extreme levels of mortality in ash (Fraxinus spp., Oleaceae) in the USA and Canada. Knowledge of buprestid chemical ecology is sparse, but the appearance of EAB in North America and its devastating ecological and economic impacts have afforded an opportunity to study its semiochemistry and biology in detail. We review the chemical ecology of EAB and the application of its sex pheromone, the female-produced (3 Z)-dodecen-12-olide ((3 Z)-lactone), and the green leaf volatile, (3Z)-hexenol, in operational surveys and experimental control strategies. Adding (3 Z)-lactone to green sticky prism traps with (3 Z)-hexenol on the south aspect of the tree canopy consistently increases trap captures and detection rates at low insect densities. This bait combination is more attractive than (3 Z)-hexenol alone, especially when traps are in a competitive deployment. Using a 'push–pull' strategy, some nonhost volatiles deployed in ash trees significantly lower trap capture and may be useful in the push component, with a girdled tree treated with systemic insecticide constituting the pull component. We review reliable branch sampling techniques to estimate incidence and density of EAB which positively correlate with trap capture. We recommend using these combined tools to detect, delimit, and monitor EAB. [ABSTRACT FROM AUTHOR]

We develop an acceptance sampling approach for surveillance of the emerald ash borer (EAB), a harmful forest pest, in Winnipeg, Canada. We compare sampling strategies computed with two different management objectives. The first objective maximizes the expected area with detected infestations and the second objective minimizes the expected number of undetected infested trees in sites that were not inspected or where inspection did not find an infestation. The choice of the management objective influences the survey strategy: achieving the first objective involves selecting sites with high infestation rates proximal to the infested area, whereas the second objective requires inspecting sites with both high infestation rates and high host densities. Adding uncertainty prescribes inspecting a larger area with lower sampling rates and extending the surveys to farther distances from the infested locations. If a decision maker wants to minimize the worst-case damage from failed detections, the optimal strategy is to survey more sites with high host densities at farther distances, where EAB arrivals could cause significant damage if not detected quickly. Accounting for the uncertainty addresses possible variation in infestation rates and helps develop a more diversified survey strategy. The approach is generalizable and can support survey programmes for new pest incursions. [ABSTRACT FROM AUTHOR]

The bronze birch borer, Agrilus anxius , is a North American buprestid pest of stressed or weakened birch trees (Betula spp.) and is considered a major threat to European birch species as a potentially adventive insect. Laboratory bioassays and field trapping experiments were conducted to elucidate potential visual and chemical cues used in host location in this species. Birch bark and foliar volatiles (Betula papyrifera Marsh) and a pheromone attractive to the congener, A. planipennis , (3 Z)-dodecen-12-olide ((3 Z)-lactone), were tested along with a girdled tree treatment, with purple sticky prism traps. Only the girdled tree treatment with purple traps elicited significant attraction by adult A. anxius. Various colours of sticky traps were tested with host volatiles attractive to A. planipennis ; results showed that unbaited green sticky traps were more attractive than other colours tested; none of the host volatiles tested increased trap capture with any traps. Examination of foliage and bark of B. papyrifera by GC/EAD, and GC/MS techniques has identified several EAD-active compounds with (3 Z)-hexenol and (5 S ,7 S)-conophthorin as the most EAD-active molecules. Neither compound, however, alone or combined, elicited significant trap capture on green sticky prism traps; these compounds may find importance as synergists once the pheromone for A. anxius is identified. [ABSTRACT FROM AUTHOR]