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The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive woodboring pest of ash trees (Fraxinus sp.) in North America. Among the Asiatic parasitoids being released for the management of EAB in North America, Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) is the only EAB egg parasitoid. To date, more than 2.5 million O. agrili have been released in North America; however, few studies have examined its success as a biological control agent of EAB. We conducted studies to assess O. agrili establishment, persistence, spread, and EAB egg parasitism rates in Michigan at the earliest release sites (2007-2010), as well as at more recent release sites (2015-2016) in 3 Northeastern United States (Connecticut, Massachusetts, New York). In both regions, we documented successful O. agrili establishment at all but one release site. In Michigan, O. agrili has persisted at release sites for over a decade and spread to all control sites located 0.6-3.8 km from release sites. Overall, EAB egg parasitism ranged from 1.5% to 51.2% (mean of 21.4%) during 2016-2020 in Michigan and from 2.6% to 29.2% (mean of 16.1%) during 2018-2020 in the Northeastern states. Future research efforts should focus on factors affecting the spatiotemporal variation in EAB egg parasitism rates by O. agrili, as well as its potential range in North America., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The emerald ash borer (EAB), Agrilus planipennis Fairmaire, a buprestid beetle native to Asia, has become a serious pest of ash trees (Fraxinus spp.) in North America since the early 2000s. Due to the impracticality of applying insecticides in natural forests, biocontrol is the most viable method to manage EAB in natural ecosystems. Here, we report the first evidence for the establishment and impact of Spathius galinae Belokobylskij & Strazenac, a larval parasitoid first released in North America in 2016 and 2017 at six mixed-hardwood forest sites, in Connecticut, New York, and Massachusetts. We also report current levels of abundance and parasitism of another introduced larval EAB parasitoid, Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae), released in 2015 and 2016 in these same sites. Spathius galinae was recovered at all release sites in 2018, and its density in sampled trees had increased 1.5- to 20-fold (relative to the first postrelease sample year), reaching a final density of 2.3-14.3 broods/m2 of phloem area and causing 13.1-49.2% marginal rate of parasitism at four of the six sites. In contrast, T. planipennisi was only recovered in 2018 at four of the six release sites, and both its density (0.1-2.3 broods/m2 of phloem area) and parasitism (0.1-5.6%) were lower than that of S. galinae throughout the study at the four sites where recoveries were made. Our data fill a critical gap in the development of a biocontrol-based EAB management plan to protect surviving ash trees capable of reaching maturity and producing replacement trees., (Published by Oxford University Press on behalf of Entomological Society of America 2019.)

Endangerment factors are reviewed for 57 U.S. federally listed insects and 116 rare eastern North American lepidopterans to determine the importance of invasive species relative to 15 other recognized endangerment factors. Invasive plants, social insects (especially ants), and vertebrate grazers and predators repeatedly were identified as groups directly or indirectly threatening native insect biodiversity. Among rare eastern North American lepidopterans, the (mostly indirect) consequences of the establishment of the gypsy moth (Lymantria dispar) surfaced as a general threat. Remote islands, especially those with high human visitation, stand out as being highly threatened by invasives. In the worst cases, impacts from invasive species cascade through a community and destabilize existing trophic interconnections and alter basic ecosystem properties, changing hydrology, nutrient cycles, soil chemistry, fire susceptibility, and light availability, and precipitate myriad other changes in biotic and abiotic parameters. Invasive ants and herbivorous insects provide some of the most dramatic examples of such insect-induced invasional cascades.

Encarsia formosa is a parasitoid used worldwide for the biological control of whiteflies on vegetables and ornamental plants grown in greenhouses. Because of outstanding success in controlling Trialeurodes vaporariorum on tomatoes, the biology and behavior of this wasp have been intensively studied to identify attributes that contribute to successful biological control and how best to manipulate augmentative releases into greenhouses to suppress whitefly population growth. In this article, we review the biology of adult and immature E. formosa, population dynamics of whitefly-parasitoid interactions, and commercial use in greenhouses. Deficits in knowledge of aspects of E. formosa's biology and use are noted.

The numbers of blacklegged tick, Ixodes scapularis Say, per hectare that engorged as larvae and nymphs on white-footed mice, Peromyscus leucopus (Rafinesque), were estimated at 3 sites in coastal Massachusetts. Estimates of numbers of engorged ticks dropping per day from trapped mice were multiplied by mark-recapture estimates of the density (numbers per hectare) of white-footed mice to estimate numbers of ticks engorging on mice per hectare. In 1991, estimates of seasonal totals per hectare of I. scapularis nymphs completing blood meals on P.leucopus ranged from 825 +/- 68 at Nonamesset to 6,654 +/- 770 at Menemsha. This absolute sampling method (the drop-off method) was compared with drag sampling for nymphal ticks. Per hectare estimation of engorgement rates overcomes a shortcoming associated with drag sampling because site-to-site comparisons can be made even where vegetation structure differs markedly among sites. The drop-off method may be used to quantify the contribution of any host to the engorged tick population, provided sufficient such hosts can be collected on a weekly basis.

The cement used by females ofSupella longipala (F.) (Orthoptera∶Blattellidae) to bind their oothecae to substrates acts as a kairomone for host acceptance by the parasitoidComperia merceti. C. merceti discriminates parasitized from unparasitized oothecae and oviposts at reduced levels in the former. Low survival rates for parasitoids reared from oothecae receiving fewer than four ovipositions suggests that an "optimal density range" for resource utilization byC. merceti exists.