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Emerald ash borer, Agrilus planipennis Fairmaire (EAB) (Coleoptera: Buprestidae), has caused devastating levels of mortality to ash trees (Fraxinus Linnaeus, Oleaceae) in North America. Early infestations of this insect are extremely difficult to detect due to cryptic larval feeding and lack of obvious signs or symptoms of initial attack. Considerable research has been conducted to develop tools and techniques aimed towards providing early detection and delimitation of populations of this invasive species. Sampling tools and techniques include: (1) relating visual signs and symptoms to the presence of EAB infestations; (2) use of girdled trap-trees to increase captures of adults and subsequent larval densities; (3) sub-sampling protocols to detect larvae under the bark based on their within-tree distribution; (4) artificial traps baited with pheromones and/or host volatiles attractive to adult EAB; (5) biosurvellience using buprestid-hunting wasps; and (6) remote sensing techniques. Additional research modelling patterns of infestation at the landscape scale indicate very clumped or aggregated distributions, greatly increasing the difficulty of early detection across large spatial scales. Further research is still required to increase the efficacy and efficiency of early detection tools and techniques, including cost/benefit analysis of the various sampling options, increased understanding of patterns of initial infestation across the landscape, development of sampling programs for both detection and delimitation, and development of sequential sampling programs to estimate EAB density. This information will enable foresters to make informed decisions regarding management strategies against this devastating pest. [ABSTRACT FROM PUBLISHER]

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Early detection of emerald ash borer (EAB) (Agrilus planipennis Fairmaire; Coleoptera: Buprestidae) infestation is problematic, with visual indicators not appearing until late during an infestation, and detection methods often requiring substantial trade-offs between information yielded and cost. Decision makers must determine which detection methods provide sufficiently valuable information that matches their objectives and adhere to budget constraints. Notably, decision makers from different organisations often have different objectives; hence their perceptions of costs and benefits of these choices can vary. Economic thought and analysis can provide useful insights for decision makers concerned with understanding and balancing costs and benefits associated with detection strategies. Here we provide a brief review of economic studies of EAB and present a conceptual framework on the detection strategy problem drawing on “information economics”. [ABSTRACT FROM PUBLISHER]

Agrilus planipennis (Coleoptera: Buprestidae), is causing extensive mortality of ash (Fraxinus Linnaeus; Oleaceae) in North America. Once detected in an area, resource managers require methods to obtain estimates that could improve management decisions. We studied the within-crown and within-branch distribution and abundance of A. planipennis feeding galleries by sampling 3-m-long branches from asymptomatic urban ash trees and subdividing each branch into 12 sections of 25 cm each. We found galleries in all 12 sections of some, but not all, branches. Section was a significant source of variation in A. planipennis gallery density/m² of branch surface area. A comparison of predictive power and efficiency of estimates for samples of increasing length, and for samples of the same length but consisting of different combinations of sections, revealed that those based on the two basal 25-cm sections of a branch from the lower-crown or mid-crown of an asymptomatic tree were less accurate and precise than those based on more sections, but were the most cost effective. Whittling more sections per branch, irrespective of the combinations of branch sections per length, improved predictive power but reduced cost effectiveness. We also observed that crown level was not important, and aspect was only marginally so, when estimating gallery abundance per sampled branch. [ABSTRACT FROM AUTHOR]

Phasgonophora sulcata Westwood (Hymenoptera: Chalcididae) is a North American parasitoid now using Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) as a novel host, and may prove useful in biocontrol. Unfortunately, information is lacking regarding mating and the presence of pheromones, which may be important when attempting to exploit this parasitoid within a management context. Herein we used olfactometer assays and behavioural observations to determine the courtship and mating sequences of P. sulcata. A significantly higher proportion of males oriented towards females over the control arm containing filtered air in an olfactometer regardless of the age classes of females or males examined. We also observed four pre-copulatory behaviours that were consistent in all mating pairs. Our results indicate that courtship may be mediated by male perception of female-produced pheromones. Understanding the courtship sequence may be useful in rearing laboratory populations, while the putative pheromones may be useful in detection and retention of P. sulcata populations. [ABSTRACT FROM PUBLISHER]

Monochamol (2-undecyloxy-1-ethanol) is a male-produced aggregation pheromone for several Monochamus Dejean (Coleoptera: Cerambycidae) species. We conducted trapping experiments in Canada, Poland, and China to test whether monochamol was attractive to additional Monochamus species and if attraction was synergised by plant volatiles and bark beetle (Coleoptera: Curculionidae) pheromones. We provide the first evidence of attraction for M. urussovii (Fischer) and M. saltuarius (Gebler) to monochamol or monochamol+kairomones. The highest numbers of M. urussovii were captured in traps baited with monochamol+plant volatiles (Manuka oil, ethanol and (95/5±) α−pinene). Captures of M. saltuarius were highest in traps baited with monochamol, with the addition of cubeb oil tending to reduce captures. The highest numbers of M. scutellatus (Say) were captured in traps baited with monochamol+kairomones. A similar pattern in trap captures was found for M. notatus (Drury), M. marmorator Kirby, M. carolinensis (Olivier), and M. mutator LeConte. Detection rates, that is, proportion of traps capturing at least one specimen, was highest for traps baited with monochamol plus kairomones, particularly for less-common species. These results support the emerging hypothesis that pheromone compounds can attract related cerambycid species with cumulative evidence for attraction to monochamol for 12 species of Monochamus worldwide. [ABSTRACT FROM PUBLISHER]

First detected in North America in 2002, the emerald ash borer (EAB) (Agrilus planipennis Fairmaire; Coleoptera: Buprestidae), an invasive phloem-feeding beetle from Asia, has killed tens of millions of ash (Fraxinus Linnaeus; Oleaceae) trees. Although few parasitoids attack EAB in North America, three parasitoid species were found attacking EAB in China: the egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) and two larval parasitoids Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) and Spathius agrili Yang (Hymenoptera: Braconidae). In 2007, classical biological control of EAB began in the United States of America after release of these three species was approved. In 2013, release of the larval parasitoids was approved in Canada. Research continues at study sites in Michigan, United States of America where the establishment, prevalence, and spread of O. agrili and T. planipennisi have been monitored since 2008. However, establishment of S. agrili remains unconfirmed in northern areas, and its release is now restricted to regions below the 40th parallel. In 2015, approval for release of Spathius galinae Belokobylskij (Hymenoptera: Braconidae), an EAB larval parasitoid from the Russian Far East, may be granted in the United States of America. Researchers are guardedly optimistic that a complex of introduced and native natural enemies will regulate EAB densities below a tolerance threshold for survival of ash species or genotypes in forested ecosystems. [ABSTRACT FROM PUBLISHER]

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a destructive invasive pest that threatens North American ash (Fraxinus (Oleaceae)) and inflicts substantial aesthetic, ecological, and economic damage in urban forests and rural woodlands. Understanding adult EAB dispersal and spread of infestations is critical to effectively manage and mitigate its potential impact in North America and elsewhere. Challenges of quantifying short-distance and long-distance movement of adult EAB in the field remain exceptionally difficult. Here we review our current understanding of EAB spread. Research to date suggests natural spread of EAB populations is variable and influenced by local environmental conditions, but limited to only a few km per year. In contrast, long-distance spread resulting from anthropogenic movement of infested ash material, such as nursery trees or firewood, can greatly increase local and regional rate of spread through the formation of satellite populations. Key areas in need of future research are highlighted. [ABSTRACT FROM PUBLISHER]

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a non-native, wood-boring beetle that has caused widespread mortality of ash (Fraxinus Linnaeus (Oleaceae)) in eastern North America. During 2004–2007, we determined whether forest community composition and structure of black (F. nigra Marshall), green (F. pennsylvanica Marshall), and white (F. americana Linnaeus) ash stands influenced their susceptibility to EAB invasion in southeast Michigan, United States of America. There was no relationship between EAB-induced ash decline or percentage mortality and any measure of community composition (tree species diversity, stand/ash density, total basal area, or relative dominance of ash). There was also no relationship between measures of EAB impact (density of EAB signs, ash decline rating, percentage ash mortality, or percentage infested ash) and forest attributes (ash/total stand density, basal area, ash importance, or stand diversity). Decline and mortality of black ash advanced more rapidly than that of white and green ash. Percentage mortality of ash increased from 51% to 93% during 2004–2007. Distance from the epicentre of the invasion was negatively correlated with ash mortality, but this relationship dissipated over time. Stand composition data suggests that ash will be replaced by Quercus Linnaeus (Fagaceae), Acer Linnaeus (Sapindaceae), and Tilia Linnaeus (Malvaceae); such vegetation changes will irreversibly alter the structure and function of these forests. [ABSTRACT FROM PUBLISHER]

Practical and effective strategies to manage emerald ash borer (EAB) (Agrilus planipennis Fairmaire; Coleoptera: Buprestidae) are increasingly important given economic and ecological impacts of this invader. While EAB detection remains challenging, tactics are available to protect individual ash (Fraxinus Linnaeus; Oleaceae) trees and slow EAB population growth, thereby delaying ash mortality. Simulations with a coupled map lattice model, parameterised with data from numerous field studies, showed treating trees with a highly effective systemic insecticide (TREE-äge™; emamectin benzoate), would be more effective in slowing EAB population growth than girdling trees to attract ovipositing females then destroying trees before larvae develop, while harvesting ash to reduce available phloem would have the least effect. From 2008 to 2012, cooperators participated in a pilot project to implement an integrated strategy for an EAB infestation in Upper Michigan, United States of America. Ash was inventoried and EAB density monitored using girdled ash detection trees supplemented with baited artificial traps across the >750 km2 project area. While only a tiny fraction of ash trees in the project area were girdled (444–855 trees annually) or injected with TREE-äge™ (<360 roadside trees annually), and treatment distribution was restricted, both treatments slowed EAB population growth. Coupling TREE-äge™ injections with other tactics will likely yield additive or synergistic outcomes. [ABSTRACT FROM PUBLISHER]

As of summer 2014, the invasive emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), has become established in 24 states in the United States of America and has killed tens of millions of ash trees since its introduction into Michigan in the 1990s. Considerable research has been conducted on many aspects of EAB life history, natural history, ecology, and management strategies in an attempt to contain this devastating pest. In this article, we review the life history, mating behaviours, and host plant selection by EAB in North America as well as host resistance to EAB attack. [ABSTRACT FROM PUBLISHER]

Emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an Asian species that was introduced into North America in the mid-1990s. The beetle has the potential to devastate populations of Fraxinus Linnaeus (Oleaceae) species. Several species of Hymenoptera parasitoids have made the transition from North American Agrilus Curtis hosts to A. planipennis, and some (e.g., Atanycolus Förster (Hymenoptera: Braconidae) species) have caused substantial mortality. Invertebrate predators of A. planipennis have been poorly investigated. Predation by woodpeckers (Aves: Picidae) has had the greatest impact on A. planipennis populations. Native entomopathogens have also been observed in populations of A. planipennis and are being explored as potential biological control agents. Agrilus planipennis is a freeze-intolerant species and as such perishes when its tissues freeze. However, the beetle can achieve a mean supercooling point of −30 °C by the production of cryoprotectants, especially glycerol. This low supercooling point in combination with temperatures higher than ambient in its overwintering microhabitat means that it can survive in most of its invaded range. As its distribution expands northward its cold hardiness may be challenged. North American species of Fraxinus possess some resistance to A. planipennis via defensive mechanisms, but these are quickly overcome by expanding larval populations. Intraspecific competition (via cannibalism and starvation) impacts larval survival. [ABSTRACT FROM PUBLISHER]

The article introduces various papers on the emerald ash borer (EAB) published within the issue, including one on the life cycle and mating behavior of the insect, another on the pheromone ecology of EAB and a paper on the classical biological control of the pest.