We conducted trapping experiments for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) in Michigan, U.S.A., and Ontario, Canada, to compare unbaited light green sticky prism traps with traps baited with phoebe oil, (Z)-3-hexenol (Z3-6:OH), or blends of other green leaf volatiles (GLVs) with Z3-6:OH. Traps were placed in the lower canopy of ash trees (Fraxinus spp.). Catches with Z3-6:OH-baited traps showed a significant male bias and these traps caught significantly more males than the unbaited controls at both sites. They were also superior to phoebe oil-baited traps and those baited with GLV blends. Catches with phoebe oil showed a significant female bias but there was no difference in the number of females captured between traps baited with phoebe oil or Z3-6:OH lures. Catches were analyzed at regular time intervals to examine the response of A. planipennis to the lures over the course of the flight season. Z3-6:OH-baited traps consistently caught more males than the controls at each interval throughout the flight season. Catches of females with Z3-6:OH and phoebe oil were significantly better than the controls early in the flight season but declined to control levels by midseason. Our results suggest that Z3-6:OH-baited green traps placed in the ash canopy would be a superior lure for detecting and monitoring A. planipennis throughout the flight season.

The emerald ash borer, Agrilus planipennis, is the most damaging invasive forest insect pest ever to have invaded North America. It is native to Asia and is established in the United States, Canada, European Russia and Ukraine where it threatens native ash across North America and Europe. We evaluated trap designs, colors, and lures for A. planipennis detection at sites with varying infestation levels. Purple or green sticky prism traps and multiple funnel traps hung in the canopy of ash trees and double-decker traps (consisting of two sticky prisms attached to a 3m vertical pole at 3m and 1.8m above ground) had high detection rates even at sites with very low infestation levels. At a low infestation site, females were more attracted to dark purple sticky prism traps hung in the canopy and to Manuka oil and Phoebe oil lures than to light green sticky prism traps or cis-3-hexenol lures; whereas, males were more attracted to light green sticky prism traps in the canopy and cis-3-hexenol lures than to dark purple sticky prism traps or Manuka and Phoebe oil lures. More males and females were captured in double-decker traps with dark green upper prisms and light purple lower prisms, baited with cis-3-hexenol, than in double-decker traps with dark purple upper and lower prisms. Dark green funnel traps and double-decker traps with dark green upper and light purple lower prisms baited with cis-3-hexenol lures captured more females than dark green sticky prism traps hung in the canopy at sites with very low infestation levels. Detection rates were similar among trap types and ranged from 75 to 80% for dark green sticky prism traps, 82.5-100% for dark green funnel traps, and 100% for double-decker traps with dark green upper and light purple lower prisms at sites with very low A. planipennis infestations. Cost, ability to reuse the traps, and ease of deployment varies among trap types. These and other factors including trap placement, host density and condition should be considered in selecting traps and designing operational surveys. Future research is needed to determine effective trapping radius, relationship of trap catches to population density, cost benefit of different trap types, and optimal deployment strategy. Greater numbers of A. planipennis captured and higher detection rates in cis-3-hexenol-baited double-decker traps with dark green upper prisms and light purple lower prisms and in dark green funnel traps compared to dark green prism traps at sites with very low infestation levels, suggest these trap types would be most effective for operational detection surveys.

Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae), an invasive phloem-feeding insect native to Asia, threatens at least 16 North American ash (Fraxinus) species and has killed hundreds of millions of ash trees in landscapes and forests. We conducted laboratory bioassays to assess the relative efficacy of systemic insecticides to control emerald ash borer larvae in winter 2009 and 2010. Second- and third-instar larvae were reared on artificial diet treated with varying doses of emamectin benzoate (TREE-äge, Arborjet, Inc., Woburn, MA), imidacloprid (Imicide, J. J Mauget Co., Arcadia, CA), dinotefuran (Safari, Valent Professional Products, Walnut Creek, CA), and azadirachtin (TreeAzin, BioForest Technologies, Inc., Sault Ste. Marie, Ontario, and Azasol, Arborjet, Inc., Woburn, MA). All of the insecticides were toxic to emerald ash borer larvae, but lethal concentrations needed to kill 50% of the larvae (LC50), standardized by larval weight, varied with insecticide and time. On the earliest date with a significant fit of the probit model, LC50 values were 0.024 ppm/g at day 29 for TREE-äge, 0.015 ppm/g at day 63 for Imicide, 0.030 ppm/g at day 46 for Safari, 0.025 ppm/g at day 24 for TreeAzin, and 0.027 ppm/g at day 27 for Azasol. The median lethal time to kill 50% (LT50) of the tested larvae also varied with insecticide product and dose, and was longer for Imicide and Safari than for TREE-äge or the azadirachtin products. Insecticide efficacy in the field will depend on adult and larval mortality as well as leaf and phloem insecticide residues.

1 Indigenous artisans in the Great Lakes region rely on the ring-porous property of black ash Fraxinus nigra Marshall (Oleaceae), which allows annual layers of xylem to be easily separated to make baskets that are important economic resources and vessels of culture. 2 The emerald ash borer Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is threatening North America's ash resource, including black ash and this centuries-old art form, resulting in grave concern about the availability of black ash trees for basketmaking and about movement of black ash (along with A. planipennis) from areas where it is cut to lands where it is pounded and split to make baskets. 3 We evaluated the traditional practice of storing black ash logs submerged in water as a possible method for killing within-tree life stages of A. planipennis at the same time as preserving the wood's value for basketmaking. 4 Black ash trees infested with overwintering A. planipennis larvae were felled and cut into 60-cm bolts in 2010 and in 2011. These were submerged in a river for different lengths of time and, after treatment, placed into rearing tubes to determine survival and adult emergence, or dissected within 24 h to determine larval mortality, and then pounded and peeled into splints to assess colour and pliability. 5 In 2010, all A. planipennis larvae had died and no adults emerged from logs submerged in spring for 10 weeks or longer, whereas some larvae survived and adults emerged from logs submerged for up to 9 weeks. 6 In 2011, submergence for 18 weeks during winter or 14 weeks in spring resulted in complete mortality of A. planipennis larvae and no emergence of adults at the same time as still preserving wood quality for basketmaking.

No abstract