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Two breeding populations of the non-native Asian longhorned beetle (Anoplophora glabripennis Motschulsky), a pest of broadleaf trees in its native China, were discovered in Ontario in 2003 and 2013, respectively. Both populations were eradicated by removing all trees injured by the beetle and all uninjured trees deemed at high risk of injury. We used data collected during this removal to study host selection. Signs of A. glabripennis injury were observed on 732 stems from seven (i.e., Acer, Salix, Populus, Betula, Ulmus, Fraxinus, and Tilia) of the 45 tree genera available. Complete beetle development was confirmed on only the first four of these seven genera. Most signs of injury were on the genus Acer and on trees with a diameter at 130 cm above ground ranging between 15 and 40 cm. On most trees, the lowest sign of injury was within 3 m of the ground or within 40% of tree height. Tree height explained 63% of the variance in the location of the lowest sign of injury. Initial attacks were typically near the middle of the tree and expanded both upward and downward with successive attacks over time. We discuss how these findings could improve survey efforts for A. glabripennis. Key words: Asian longhorned beetle, host availability, host range, Acer, forest invasive alien pest, urban forest pest, exotic, eradication. Deux populations reproductrices non indigenes du longicorne asiatique (Anoplophora glabripennis Motschulsky), un ravageur des essences feuillues en Chine d'ou il est originaire, ont ete decouvertes en Ontario respectivement en 2003 et 2013. Les deux populations ont ete eradiquees en eliminant tous les arbres endommages par le longicorne et tous les arbres non endommages mais juges a risque de l'etre. Nous avons utilises les donnees collectees lors de cette intervention pour etudier la selection de l'hote. Des signes de degats causes par A. glabripennis ont ete observes sur 732 tiges appartenant a sept (c.-a-d. Acer, Salix, Populus, Betula, Ulmus, Fraxinus, et Tilia) des 45 genres d'arbres pouvant servir d'hotes. Le developpement complet de l'insecte n'a ete confirme que sur les quatre premiers de ces sept genres. La plupart des signes de degats ont ete observes sur le genre Acer et sur des arbres dont le diametre a 130 cm au-dessus du sol mesurait entre 15 et 40 cm. Sur la plupart des arbres, le signe de degat le plus bas etait situe a moins de 3 m du sol ou 40% de la hauteur de l'arbre. La hauteur de l'arbre expliquait 63% de la variance de la localisation du signe de degats le plus bas. Les attaques initiales etaient typiquement situees pres du milieu de l'arbre et s'etendaient avec le temps vers le haut et vers le bas a la suite d'attaques successives. Nous discutons de la facon dont ces resultats pourraient ameliorer les efforts d'inventaire de A. glabripennis. [Traduit par la Redaction] Mots-cles : longicorne asiatique, disponibilite des hotes, aire de repartition des hotes, Acer, ravageur forestier exotique invasif, ravageur forestier en milieu urbain, exotique, eradication., Introduction A large proportion of non-native terrestrial arthropods that arrive in Canada feed on woody plants (Langor et al. 2009). One of these alien invasive species is the Asian longhorned [...]

Adelges tsugae Annand (Hemiptera: Adelgidae) has caused extensive mortality of hemlocks (Tsuga (Endlicher) Carrière; Pinaceae) in the eastern United States of America and was discovered recently in Nova Scotia, Canada. We evaluated the use of a Velcro-covered racquetball as a sampling device for A. tsugae wool. Specifically, we report on improvements to an earlier design and evaluate several factors seen in routine sampling that influence the ability of the ball to trap and retain adelgid wool. Velcro was found to be critical for trapping and retaining adelgid wool on the ball during flight and landing. Wooden beads, inserted in the ball, reduced deflection during flight and bounce during landing. Higher probability of trapping wool on the ball was associated with an ascent through the crown, with increasing diameter and density of ovisacs on branch tips, and with increasing abundance of woolly twigs on the forest floor. Higher probability of retaining wool on the ball was associated with Velcro surface area and with amount and location of wool loaded on the ball. These modifications improved detection surveys for A. tsugae in general. [ABSTRACT FROM AUTHOR]

Uncertainty about future spread of invasive organisms hinders planning of effective response measures. We present a two-stage scenario optimization model that accounts for uncertainty about the spread of an invader, and determines survey and eradication strategies that minimize the expected program cost subject to a safety rule for eradication success. The safety rule includes a risk standard for the desired probability of eradication in each invasion scenario. Because the risk standard may not be attainable in every scenario, the safety rule defines a minimum proportion of scenarios with successful eradication. We apply the model to the problem of allocating resources to survey and eradicate the Asian longhorned beetle (ALB, Anoplophora glabripennis) after its discovery in the Greater Toronto Area, Ontario, Canada. We use historical data on ALB spread to generate a set of plausible invasion scenarios that characterizes the uncertainty of the beetle’s extent. We use these scenarios in the model to find survey and tree removal strategies that minimize the expected program cost while satisfying the safety rule. We also identify strategies that reduce the risk of very high program costs. Our results reveal two alternative strategies: (i) delimiting surveys and subsequent tree removal based on the surveys' outcomes, or (ii) preventive host tree removal without referring to delimiting surveys. The second strategy is more likely to meet the stated objectives when the capacity to detect an invader is low or the aspirations to eradicate it are high. Our results provide practical guidelines to identify the best management strategy given aspirational targets for eradication and spending. [ABSTRACT FROM AUTHOR]

During the eradication program undertaken against Anoplophora glabripennis (Motschulsky) in the Greater Toronto Area, information was collected on the numerous signs of injury found on wounded trees. Herein, we used a portion of this information to assess the characteristics of logs with signs of oviposition (i.e., pits). Specifically, we related the basal diameter, type (log bole vs. log branch), height above ground, and branch hierarchy level of logs with pits to tree size (i.e., height and diameter at breast height) and level of infestation intensity. In general, pits were concentrated on logs from the bole and branches that were 8-14 cm in diameter in the lower 8 m of the bole and in the first 2 levels of the branching hierarchy. Oviposition pit location was strongly influenced by tree size-both height and diameter at breast height, with more pits on the lower bole in small trees and then higher on the bole and into the branches as tree size increased. As tree-level infestation intensity increased, pits were found on both larger and smaller diameter portions of the trees, presumably as preferred oviposition sites became saturated. These findings can improve the efficacy of surveillance activities for A. glabripennis., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)