Supporting transition to integrated pest management in pear and apple with education and training in European earwig releases

Project Overview

Project Type: Local Ed & Demo (formerly RGR)
Funds awarded in 2023: $100,000.00
Projected End Date: 03/31/2026
Host Institution Award ID: G294-23-W9988
Grant Recipient: Washington State University
Region: Western
State: Washington
Principal Investigator:
Dr. Robert Orpet
Washington State University

Information Products


  • Fruits: apples, pears


  • Education and Training: demonstration, extension, farmer to farmer, technical assistance, workshop
  • Pest Management: biological control, field monitoring/scouting, integrated pest management

    Proposal abstract:

    Integrated pest management (IPM) is a framework to consider all available tools to sustainably reduce crop damage from pests. In Washington and Oregon, which together comprise most of United States pear and apple acreage, several pests are being managed unsuccessfully due to over-use of pesticides disrupting biocontrol (pest suppression from predators). Pear orchards often apply over 10 insecticide sprays per season at a cost of $2,500 per acre while failing to prevent pear psylla damage, while apple orchardists are turning to diazinon to kill woolly apple aphid despite industry-wide desire to move away from organophosphate pesticides.

    There is evidence that integrated strategies that conserve biological agents through wise timing and selection of pesticide sprays keep pear psylla and woolly apple aphid suppressed. A major challenge to adopting these strategies is a multi-year lag in establishment of biological control agents. Insecticide-based management strategies usually extirpate European earwig, a key biological control agent of both pear psylla and woolly apple aphid. This predator has low dispersal ability and will not quickly recolonize orchards once a spray program is revised for biocontrol compatibility.

    We propose to support greater transition to integrated pest management in pear and apple with education and training in European earwig releases. Previous projects developed methods to collect and release European earwigs to establish populations in orchards and suppress pests. Our team will share this knowledge with educational presentations and dissemination of educational materials. We will host workshops where stakeholders can collect their own earwigs to release in orchards and report back with monitoring data. This project will reduce roadblocks to adopting integrated pest management and improve pest suppression, saving growers money and increasing their profits while reducing use of environmentally harmful pesticides with human health risks.

    Project objectives from proposal:

    Objective 1: Increase knowledge of how to successfully integrate biocontrol in pear and apple pest management, especially in the role of European earwigs and how to conserve them.

    • Measure increase in knowledge among at least 200 stakeholders in each of Wenatchee (year 1), and in Wenatchee, Yakima, and Hood River (year 2) regions after educational presentations.
    • Increase awareness of predators and parasitoids via three newsletter articles for Tree Fruit Matters, distributing field notebooks with biocontrol pictures and facts to 700 stakeholders across the three regions, and managing a project webpage similar to Orpet et al. (2022).

    Objective 2: Facilitate and train tree fruit professionals to monitor, collect, and transport earwigs to inoculate orchards lacking earwigs and increase biocontrol services.

    • Document ability of at least 80 stakeholders to collect earwigs at workshops across the three regions and two years.
    • Measure success of earwig releases and ability of workshop attendees to monitor earwigs with reports from each person the following year (years 2 and 3).

    Objective 3: Increase the number of pear and apple acres using IPM by facilitating the documentation of outcomes and the sharing of results.

    • Share at one presentation targeted to each of the three regions and via an open-access peer-reviewed article earwig data from participating stakeholders to show that the predator was established in IPM orchards.
    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.