Emerald Ash Borer (Coleoptera: Buprestidae) Attraction to Stressed or Baited Ash Trees

Abstract

Emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), has killed millions of ash (Fraxinus sp.) trees in North America since its discovery in Michigan in 2002. Efficient methods to detect low-density A. planipennis populations remain a critical priority for regulatory and resource management agencies. We compared the density of adult A. planipennis captured on sticky bands and larval density among ash trees that were girdled for 1 or 2 yr, wounded, exposed to the stress-elicitor methyl jasmonate, baited with Manuka oil lures, or left untreated. Studies were conducted at four sites in 2006 and 2007, where A. planipennis densities on untreated trees ranged from very low to moderate. In 2006, 1-yr girdled trees captured significantly more adult A. planipennis and had higher larval densities than untreated control trees or trees treated with methyl jasmonate or Manuka oil. Open-grown trees captured significantly more A. planipennis beetles than partially or fully shaded trees. In 2007, A. planipennis population levels and captures of adult A. planipennis were substantially higher than in 2006. The density of adults captured on sticky bands did not differ significantly among canopy exposure classes or treatments in 2007. Larval density was significantly higher in untreated, wounded, and 1-yr girdled trees (girdled in 2007) than in 2-yr girdled trees (girdled in 2006), where most phloem was consumed by A. planipennis larvae the previous year. A total of 36 trees (32 in 2006, 4 in 2007) caught no beetles, but 16 of those trees (13 in 2006, 3 in 2007) had A. planipennis larvae. In 2006, there was a positive linear relationship between the density of adults captured on sticky bands and larval density in trees. Our results show that freshly girdled and open grown trees were most attractive to A. planipennis, especially at low-density sites. If girdled trees are used for A. planipennis detection or survey, debarking trees to locate larval galleries is crucial.

Integrodifference equations in patchy landscapes

“…In recent years, many of these studies have been published (e.g. see Anulewicz et al, 2007;Mastro et al, 2007;McCullough and Siegert, 2007;Lyons et al, 2009;McCullough et al, 2009) and thus provide us with an avenue to estimate the parameters in system (6.2.1). For each parameter, we define a pointestimate (or default value) and a range for sensitivity analysis.…”

Forest Health Management and Detection of Invasive Forest Insects

“…Currently, key survey methods include the use of external signs and symptoms, green and purple sticky prism traps baited with ash volatile lures, green multi-funnel traps, trap logs, and using girdled trap trees which are an expensive and destructive method [15,88,92,95]. Trap trees involve girdling (removing a band of bark and phloem from around the tree) individual trees which become attractive to the adult beetles [86,87]. After one to two years the tree is felled and debarked in autumn to inspect for EAB larvae and S-shaped galleries [96].…”

“…There also appears to be adult preference for rough-barked trees over smooth-barked trees and will generally target trees grown in open conditions compared to shaded conditions [77,86,87]. Adults are also attracted to specific shades of green and purple [88].…”

“…Host volatiles produced by ash are attractive to adult beetles and bark sesquiterpenes and green leaf volatiles have been identified [78,[89][90][91]. These volatiles often increase with host stress and girdled ash trees in particular are highly attractive to adult EAB [86,87,89,91].…”

Challenges of managing the emerald ash borer: What do managers want, and what can researchers tell them?

“…In both studies, respondents had good familiarity with the type of control options used in Canada (i.e., insecticides, biological control and silviculture) and they were aware of methods not widely used in Canada (e.g., girdled trap trees; McCullough et al 2009a). However, they were not necessarily aware of the specific products and tactics available to them (i.e., which insecticides were registered for use in Canada).…”