Attraction of the emerald ash borer to ash trees stressed by girdling, herbicide treatment, or wounding

Abstract

New infestations of emerald ash borer, Agrilus planipennis Fairmaire, an invasive pest native to Asia, are difficult to detect until densities build and symptoms appear on affected ash (Fraxinus spp). We compared the attraction of A. planipennis to ash trees stressed by girdling (bark and phloem removed from a 15 cm wide band around the tree (2003)(2004)(2005)), vertical wounding (same area of bark and phloem removed in a vertical strip (2004)), herbicide treatment (Pathway applied with a Hypo-Hatchet tree injector (2003) or basal bark application of Garlon 4 (2004Garlon 4 ( , 2005), exposure to the volatile stress elicitor methyl jasmonate (2005), or left untreated (2003-2005). The number and density of captured adults and density of larvae were recorded for 24, 18, and 18 replicates of each treatment at four, three, and five sites in 2003, 2004, and 2005, respectively. Girdled trees generally captured more adult A. planipennis and consistently had higher larval densities than untreated trees, and at most sites, than trees stressed by other treatments. Differential attraction to girdled trees was more pronounced at sites with lower densities of A. planipennis. Rates of capture of adults and densities of larvae were higher on trees in full or nearly full sun than on shaded trees. Girdled trees could be a useful tool for use in operational programs to detect or manage localized A. planipennis infestations.Résumé : Les nouvelles infestations de l'agrile du frêne, Agrilus planipennis Fairmaire, un ravageur invasif, indigène de l'Asie, sont difficiles à détecter jusqu'à ce que la densité de l'insecte augmente et que les symptômes apparaissent sur les frênes (Fraxinus spp.) infestés. Nous avons comparé l'attirance d'A. planipennis pour des tiges de frêne stressées par une annélation (bande d'écorce et de phloème de 15 cm enlevée autour de la tige de 2003 à 2005; une blessure verticale (bande verticale d'écorce et de phloème enlevée sur une surface équivalente (2004)); l'application d'un herbicide (Pathway appliqué avec une hachette injectrice (2003)); l'application de Garlon sur l'écorce à la base du tronc (2004)(2005)); l'exposition au jasmonate de méthyle, un éliciteur de stress volatil (2005) et pour des tiges non traitées (2003 à 2005). Le nombre et la densité des adultes capturés ainsi que la densité des larves ont été notés pour 24, 18 et 18 répétitions de chaque traitement à quatre, trois et cinq endroits respectivement en 2003, 2004 et 2005. Les tiges annelées ont permis de capturer généralement plus d'A. planipennis adultes et avaient une densité de larves constamment plus élevée que les tiges non traitées et, à la plupart des endroits, que les arbres stressés par les autres traitements. L'attirance pour les tiges annelées était plus prononcée aux endroits où la densité d'A. planipennis était plus faible. Les captures d'adultes et la densité des larves étaient plus élevées sur les arbres exposés au plein soleil ou presque que sur les arbres ombragés. Des arbres annelés pourraient être un outil utile dans le...

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?

“…Most of the workshop participants were aware of the various tools and techniques that have been developed to facilitate detection, identification and delimitation of EAB infestations (e.g., Lelito et al 2008, McCullough et al 2009b, Poland et al 2011, Francese et al 2012, Dominque et al 2014, Legg et al 2014. In contrast to the workshop participants, some interviewees, including those who would be responsible for EAB management, were not aware of the tools available to them.…”

Parasitoid Guilds ofAgrilusWoodborers (Coleoptera: Buprestidae): Their Diversity and Potential for Use in Biological Control

“…Management for the invasive (exotic) Agrilus woodborers (EAB and GSOB) in the United States initially focused on attempted eradication but changed to integration of several approaches when eradication failed to reduce the pests' populations in infested areas and slow spread of the pests to the noninfested areas [12,13]. In some cases, control methods being used include delimitation of infested areas, regulatory restriction of movement of pest-infested wood or plant materials, insecticide treatment or physical destruction of infested trees [12][13][14], and biological control via introduction and release of natural enemies collected from pests' native ranges [7,[15][16][17][18]. Although none of these approaches individually is adequate, biological control, which relies on self-propagating and dispersing natural enemies, has potential to reduce invasive pest populations, particularly in forests [19][20][21].…”