BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), has killed millions of ash (Fraxinus spp.) trees across North America. Classical biological control using introductions of parasitoid wasps may provide a sustainable approach to managing this invasive insect. However, the establishment of parasitoids in the southern United States has been difficult. The phenology of emerald ash borer was studied in central North Carolina to inform biological control efforts that better align with the seasonal availability of susceptible emerald ash borer life stages in the warm climate of this region. Biweekly emerald ash borer life stage assessments were conducted in stands of infested green ash (Fraxinus pennsylvanica Marshall, Lamiales: Oleaceae) over 26 consecutive months (June 2019 through August 2021). Adult trapping was also conducted in these stands in the spring and summer of 2019, 2020, and 2021. Based on these collections, emerald ash borer exhibits a univoltine (1-yr) life cycle. Parasitoid-susceptible larvae (third and fourth instars in galleries) are present from late June through October (~1,100–3,000 degree days base 10ºC) and are mostly absent during the remainder of the year. Parasitoid release timings and the life history of selected parasitoid species should be aligned with this window of host availability to be effective. This characterization of emerald ash borer phenology and voltinism will help improve the timing and effectiveness of management efforts as this forest pest continues to spread in southern North America.

The hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), is a pest of eastern and Carolina hemlocks (Tsuga canadensis (L.) Carrière and Tsuga caroliniana Engelmann, respectively) in the eastern United States and has already caused catastrophic changes to eastern forests. As one of the significant exotic forest pests, it is imperative that the basic biology of hemlock woolly adelgid be understood for use in novel and improved management techniques. Scanning and transmission electron microscopy and enzyme assays were used to elucidate the feeding biology of hemlock woolly adelgid and are discussed in the context of the pest—plant interactions and the implications for host plant resistance. Morphological characters indicate that hemlock woolly adelgids may use labial sensilla and neural canals within the mandibular stylets to guide their stylets through close-range host acceptance processes. Stylet bundle insertion is likely assisted by external sheath material that secures the stylet bundle to the plant surface and mandibular dentitions that may assist entry into or within plant tissues. In addition, results support the theory that extra-oral digestion is likely used by hemlock woolly adelgid, suggested by both a narrow food canal and the presence of four trophically related enzymes (a trypsin-like enzyme, an amylase-like enzyme, peroxidase, and polyphenol oxidase). The presence of these enzymes also has implications for causing a systemic response in host trees.

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