Evaluating the push-pull strategy in eastern apple orchards: verbenone effectively reduces ambrosia beetle populations without the need for a pull factor in a species-specific manner

Authors: TOBIN, KELSEY - Cornell University; PEELER, SAMUEL - Cornell University; YILMAZ, AARON - Former ARS Employee; Baniszewski, Julie; KRAWCZYK, GREG - Pennsylvania State University; Ranger, Christopher; RIVERA, MONIQUE - Cornell University

Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/18/2025
Publication Date: 3/12/2025
Citation: Tobin, K., Peeler, S., Yilmaz, A., Baniszewski, J.A., Krawczyk, G., Ranger, C.M., Rivera, M. 2025. Evaluating the push-pull strategy in eastern apple orchards: verbenone effectively reduces ambrosia beetle populations without the need for a pull factor in a species-specific manner. Pest Management Science. Article ps.8755. https://doi.org/10.1002/ps.8755.
DOI: https://doi.org/10.1002/ps.8755

Interpretive Summary: Exotic ambrosia beetles are destructive wood-boring pests of apple trees (Malus domestica). Previous studies have demonstrated that all three beetle species are repelled by verbenone and strongly attracted to ethanol. We tested a “push-pull” management strategy in New York, Pennsylvania, and Ohio apple orchards with a history of ambrosia beetle damage using verbenone sachets to “push” beetles away from apple trees and high release ethanol lures to “pull” them into annihilative clear sticky traps. The most abundant exotic species captured in the study were Xylosandrus germanus and Anisandrus maiche in Ohio and New York and Xylosandrus crassiusculus in Pennsylvania. Results from field trials determined that the “push” treatment (verbenone only) reduced beetle captures. However, we did not see an increased reduction in beetle capture when “push-pull” components were paired. These results indicate that an attractive “pull” component may not be necessary to manipulate ambrosia beetles as part of behavioral management tactics. Deploying verbenone within orchard rows closest to woodlot edges can significantly reduce beetle migration into the orchard.

Technical Abstract: Non-native ambrosia beetles (Coleoptera: Curculionidae: Scolytinae), specifically Xylosandrus germanus (Blandford), Xylosandrus crassiusculus (Motschulsky), and more recently Anisandrus maiche (Kurentzov) are destructive wood-boring pests of trees of apple (Malus domestica). Previous studies have demonstrated that all three beetle species are repelled by verbenone and strongly attracted to ethanol. We tested a “push-pull” management strategy in New York, Pennsylvania, and Ohio apple orchards with a history of ambrosia beetle damage using verbenone sachets to “push” beetles away from apple trees and high-release ethanol lures to “pull” them into annihilative clear sticky traps. Three treatment plots were established and replicated twice in each state: (a) ethanol only (“pull”), (b) verbenone only (“push”), and (c) ethanol + verbenone (“push-pull”). In each experimental plot, we used low-dose ethanol traps to monitor for beetle activity. High-release ethanol traps were deployed along the woody edge of orchards in the “push” and “push-pull” treatments, verbenone sachets were deployed in rows one and three of the orchard edge closest to the woodlot in the “pull” and “push-pull” treatments, and low release ethanol traps were placed in rows two and four of all treatment blocks. The most abundant species captured in the study were X. germanus and A. maiche in Ohio and New York and X. crassiusculus in Pennsylvania. Our results show that the “push” treatment (verbenone only) significantly reduced beetle captures from the “pull” only. However, we did not see an increased reduction in beetle capture when “push-pull” components were paired. Deploying verbenone within orchard rows closest to woodlot edges can significantly reduce beetle migration into the orchard.