Buprestidae, Cerambycidae, and Scolytidae Associated with Successive Stages of \u3ci\u3eAgrilus Bilineatus\u3c/i\u3e (Coleoptera: Buprestidae) Infestation of Oaks in Wisconsin

The species of Buprestidae, Cerambycidae, and Scolytidae found in association with Agrilus bilineatus (Weber) in declining oaks, Quercus spp., in Wisconsin, were Chrysobothris femorata (Olivier) and Dicerca sp. (Buprestidae); Amniscus macula (Say),Cyrtaphorus verrucosus (Olivier), Euderces picipes (Fabricius), Graphisurus fasciatus (DeGeer), Neodytus acuminatus (Fabricius), Sarosesthes fulminans (Fabricius), and Xylotrechus colonus (Fabricius) (Cerambycidae); and Monarthrum fasciatum (Say), Monarthrum mali (Fitch), Pseudopityophthorus minutissimus (Zimmerman), and Xylaterinus politus (Say) (Scolytidae). In general, weakened oaks were first attacked by A. bilineatus. and at times that same year by C. femorata. G. fasdalus, and P. minutissimus. Infestation by M.fasciatum, M. mali, and X. politus began the season following first attack by A. bilineatus. With the exception of A. bilineatus, the above mentioned Buprestidae and Cerambycidae appeared to preferentially infest dead wood, often those portions that had died the previous season

Historical Population Increases and Related Inciting Factors of Agrilus anxius, Agrilus bilineatus, and Agrilus granulatus liragus (Coleoptera: Buprestidae) in the Lake States (Michigan, Minnesota, and Wisconsin)

Three native species of tree-infesting Agrilus have regularly reached outbreak levels in the Lake States (Michigan, Minnesota, and Wisconsin), including A. anxius Gory (bronze birch borer), A. bilineatus (Weber) (twolined chestnut borer), and A. granulatus liragus Barter & Brown (bronze poplar borer). The main host trees for these Agrilus are species of Betula for A. anxius, Castanea and Quercus for A. bilineatus, and Populus for A. granulatus liragus. Based on 197 annual forest health reports for Michigan (1950–2017, 66 years), Minnesota (1950–2017, 64 years), and Wisconsin (1951–2017, 67 years), A. bilineatus was the most often reported Agrilus species in all three states (mentioned in 90 annual reports), with A. anxius second (71 reports) and A. granulatus liragus third (21 reports). Drought was the most commonly reported inciting factor for outbreaks of all three Agrilus species, with defoliation events ranking second. The top two defoliators reported as inciting outbreaks of each species were, in decreasing order, Fenusa pumila Leach (Hymenoptera: Tenthredinidae; birch leafminer) tied with Malacosoma disstria Hübner (Lepidoptera: Lasiocampidae; forest tent caterpillar) for A. anxius; M. disstria and Alsophila pometaria (Harris) (Lepidoptera: Geometridae; fall cankerworm) for A. bilineatus; and M. disstria and Choristoneura conflictana (Walker) (Lepidoptera: Tortricidae; large aspen tortrix) for A. granulatus liragus. Other environmental factors occasionally listed as inciting Agrilus outbreaks included late spring frosts, ice storms, and strong wind events

Efficacy of Three Insecticides Applied to Bark to Control \u3ci\u3eAgrilus Planipennis\u3c/i\u3e (Coleoptera: Buprestidae)

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious exotic pest of ash (Fraxinus) trees in North America. In 2003 and 2004, we tested the efficacy of different insecticides sprayed on the bark of cut ash logs for killing emerging EAB adults. Logs (means: length = 30 cm; diam. = 16 cm) were cut from infested ash trees and treated prior to adult emergence. In 2003, we applied imidacloprid at 2 times its label rate to logs 5 days before adults began emerging from logs stored indoors. No adults successfully emerged from the imidacloprid treated logs, while an average of 108 adults per m2 emerged from untreated control logs. In 2004, we tested perme- thrin and bifenthrin at their label rates, and imidacloprid at its label rate and at 2 times its label rate. Logs (means: length = 25 cm; diam. = 12 cm) infested with EAB and stored outdoors were sprayed once or twice 4-5 wk prior to adult emergence; or once or twice 1-2 wk prior to adult emergence. Overall, mean percent adult mortality was higher for treated logs (90% mortality) compared to control logs (17%). Logs that received two applications had significantly higher mean percent mortality compared with logs that received one application. There was no significant difference in percent adult mortality among the three chemicals tested or between timing of application. In conclusion, permethrin, imidacloprid and bifenthrin were very effective at killing adult EAB emerging from cut logs, and were most effective when applied twice 1-5 wk prior to initial adult emergence

\u3ci\u3eTomicus Piniperda\u3c/i\u3e (Coleoptera: Scolytidae): Is Shoot Feeding Required for Reproductive Maturation?

The pine shoot beetle, Tomicus piniperda (Coleoptera: Scolytidae), is a univoltine pest of pine in its native range of Europe and Asia. Tomicus piniperda is now widely established in the Great Lakes region and poses a potentially significant threat to other pine-producing areas in North America. An unusual aspect of the life history of T. piniperda is the extended period of maturation-feeding that takes place in the shoots of living pine trees and subsequent overwintering before adults reproduce the following year. We investigated the extent to which shoot-feeding is required by newly-emerged T. piniperda before introduction into Scotch pine (Pinus sylvestris) logs and before any overwintering, in order for successful reproduction to occur. Tomi­cus piniperda F1 adults successfully reproduced in pine logs in the laboratory after either no shoot-feeding or after 2 to 10 weeks of shoot-feeding. Thus, it is theoretically possible for T. piniperda to be multivoltine, yet it remains univoltine

Can Emerald Ash Borer, \u3ci\u3eAgrilus Planipennis\u3c/i\u3e (Coleoptera: Buprestidae), Emerge From Logs Two Summers After Infested Trees Are Cut?

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of ash trees (Fraxinus spp.) in North America. Much of EAB’s range expansion has been attributed to human-assisted movement of infested items such as ash logs and firewood. It is unclear the amount of time that logs cut from live EAB-infested ash trees should be restricted from movement until they are no longer capable of producing viable EAB adults. In March and April 2004, we cut log sections from EAB-infested green ash (F. pennsylvanica Marsh) trees in Ann Arbor, Washtenaw County, Michigan. Log sections (mean length = 24.8 cm; diam. = 11.6 cm) were stood upright on one cut end and stored beneath a hardwood forest canopy. Adult EAB were allowed to freely emerge from log sections during summer 2004. When logs were dissected in November 2004 to January 2005, approximately one half of the total EAB life stages that were present in the logs were dead, while the other half either emerged as adults in summer 2004 or were live prepupae. Also, adults emerged from a subset of these log sections when reared in the laboratory in January to February 2005. These data suggest that EAB adults can emerge from logs for two successive emergence periods after infested ash trees have been cut

\u3ci\u3eTomicus Piniperda\u3c/i\u3e (Coleoptera: Scolytidae) Reproduction and Behavior on Scotch Pine Christmas Trees Taken Indoors

Tomicus piniperda, the pine shoot beetle, is an exotic insect that was first found in North America in 1992. A federal quarantine currently restricts movement of pine products, including Christmas trees, from infested to uninfested counties. We conducted a study to determine if T. piniperda would re- produce in Christmas trees that were cut and taken indoors during the Christmas season. Twelve Scotch pine, Pinus sylvestris, Christmas trees infested with overwintering T. piniperda beetles were cut in Indiana in early December 1993 and taken to Michigan. Four trees were dissected immediately, while the other 8 trees were taken indoors, placed in tree stands, and watered regularly. After 4 weeks indoors, 4 trees were dissected, and the other 4 were placed outdoors in Michigan for 7 weeks. Upon dissection, all overwintering sites occurred along the lower trunk within the first 40 em of the soil line; 81% were found within 10 em of the soil line. Adults collected from the 4 trees dissected in December produced viable progeny adults when placed on Scotch pine logs in the laboratory. Overwintering beetles became active and laid eggs in 4 of the 8 trees that had been taken indoors. All adults and progeny found in the 4 trees that had been placed outdoors for 7 weeks during cold January and February temperatures were dead. Overall, T. piniperda can become active and breed in Christmas trees that are cut and taken indoors in December. Tomicus piniperda survival in trees that are discarded outdoors at the end of the Christmas season will depend largely on the prevailing temperatures

Comparison of Different Trap Colors and Types for Capturing Adult \u3ci\u3eAgrilus\u3c/i\u3e (Coleoptera: Buprestidae) and Other Buprestids

Numerous research studies have focused on the development of effective traps for surveying and monitoring for emerald ash borer, Agrilus planipennis (Fairmaire) (Coleoptera: Buprestidae), since it was discovered in North America. However, little attention has been placed on developing effective traps for monitoring and surveying other Agrilus and Buprestidae. In 2009–2011, we conducted several studies to test the attractiveness of different trap colors and types of sticky traps to Agrilus and other Buprestidae. We found green (peak reflectance: 530–536 nm, 57.6%) sticky traps that consisted of custom colored corrugated plastic, and were coated with insect trapping glue to be the most effective traps for capturing the most Agrilus individuals and species. These same green traps were also effective at capturing other buprestid genera, with the exception of Chrysobothris which were most attracted to purple sticky traps. In 2012, we conducted a study to compare the three most effective sticky traps from our 2009–2011 studies along with black and green (530 nm, 57% reflectance) multifunnel traps for capturing Agrilus and other Buprestidae. Overall, we found CoroplastTM green sticky traps to be the most effective traps for capturing the most Agrilus individuals. Green multifunnel traps captured more buprestids compared to black multifunnel traps. In addition, green multifunnel traps captured the most Agrilus species

Observations of the Biology of \u3ci\u3ePhasgonophora Sulcata\u3c/i\u3e (Hymenoptera: Chalcididae), a Larval Parasitoid of the Twolined Chestnut Borer, \u3ci\u3eAgrilus Bilineatus\u3c/i\u3e (Coleoptera: Buprestidae), in Wisconsin

Phasgorzophora sulcata Westwood was the principal larval parasitoid of Agrilus bilineatus (Weber) during a study conducted in a natural oak-hardwood forest in the Kettle Moraine State Forest, Jefferson County, Wisconsin. Mean percent larval parasitism was 10.5%. Mean A. bilineatus and P. sulcata densities were, respectively, 53.0 and 6.1 adults per square meter of bark. The theoretical developmental threshold temperatures for over- wintering A. bilineatus and P. sulcata larvae were 17.8 and 19.l0C, respectively. The peak flight period of P. sulcata (9 July 1980) occurred ca. 3 weeks after the A. bilineatus peak flight (18 June 1980) at about the time of peak A. bilineatus egg eclosion. The P. sulcata sex ratios (malexfemales) for laboratory-reared and field-captured adults were 1:1.35 and 1:3.22, respectively

New State Distribution and Host Records of North American Buprestidae (Coleoptera)

The following new state records are reported for buprestid species in the eastern United States: Agrilus egeniformis Champlain and Knull and Polyceta elata LeConte from Georgia, Agrilus defectus LeConte and Agrilus vittaticollis (Randall) from Minnesota and Agrilus paramasculinus Champlain and Knull from Michigan and Indiana. Chrysobothris shawnee Wellso and Manley and Chrysobothris rugosiceps Melsheimer are reported from red oak (Quercus rubra L.) and English oak (Quercus robur L.) for the first time, after being reared from naturally infested host material collected in Michigan, USA

\u3ci\u3eTomicus Piniperda\u3c/i\u3e (Coleoptera: Scolytidae) Reproduction and Development in Scots, Jack, Red and Eastern White Pine Under Laboratory Conditions

The pine shoot beetle, Tomicus piniperda (L.) (Coleoptera: Scolytidae), is an exotic bark beetle in North America that was first found in the Great Lakes region in 1992. We evaluated T. piniperda reproduction and development in one Eurasian pine (Scots pine, Pinus sylvestris L.) and three North American pines (jack pine, P. banksiana Lamb.; red pine, P. resinosa Ait.; and eastern white pine, P. strobus L.) under laboratory conditions. We introduced one pair of adults into individual pine bolts, allowed development, collected brood, and later debarked all bolts and measured galleries. Reproduction and development occurred in all pine species tested. Mean phloem thickness varied significantly among the bolts used to represent the four pine species; it was thickest in red pine (1.3 mm) and thinnest in jack pine (0.6 mm). Linear regression analysis indicated that initial brood production (larval galleries per cm of egg gallery) increased significantly with increasing phloem thickness (r2 = 0.36), using the pooled data set for all four pine species. Using phloem thickness as a covariate, mean initial brood density (larval galleries per cm of gallery) was significantly highest on red pine, intermediate on Scots pine and white pine, and lowest on jack pine. Overall brood survival was highest on Scots pine (86%) and lowest on jack (72%) and white pine (76%); phloem thickness was not a significant covariate in this analysis