Surveying the distribution of introduced wireworms in Washington State and evaluating trap cropping as a low-cost management option

Project Overview

Project Type: Professional + Producer
Funds awarded in 2018: $49,576.00
Projected End Date: 03/31/2022
Grant Recipient: Washington State University Extension
Region: Western
State: Washington
Principal Investigator:
Dr. Brook Brouwer
Washington State University Extension

Information Products


  • Vegetables: greens (lettuces)


  • Education and Training: extension, on-farm/ranch research, workshop
  • Pest Management: field monitoring/scouting, trap crops
  • Production Systems: organic agriculture

    Proposal abstract:

    Wireworms, the larval stage of click beetles (Coleoptera: Elateridae), can cause substantial
    damage to a wide range of agronomic and vegetable crops. Two introduced species of wireworm
    (Agriotes spp.), have spread in Washington resulting in serious economic damage to high value
    vegetable crops. Wireworms thrive on pasture and grain rotations, which are commonly used by
    growers to maintain and build soil organic matter. Growers in western Washington have
    indicated that wireworms are a primary pest challenge and options for control of this pest are
    very limited. Using a preferred host as a trap crop planted near the cash crop is a potential low
    cost, environmentally friendly option for wireworm management. Using lettuce as a model crop,
    project personnel and cooperating farmers will evaluate trap cropping with wheat as compared to
    a spinosad bait product and a no management control. This project will also document current
    Agriotes distribution in Washington State using pheromone traps.
    The project team includes agricultural professionals with extensive experience in conducting onfarm
    research as well as a group of experienced vegetable growers who are proactively engaged
    in efforts to improve wireworm management. Project results will be shared directly with
    producers and agricultural professionals. Project personnel will hold on-farm field days to
    facilitate exchange of information between host farmers and with other producers in the region.
    Outreach efforts will also include presentations at established events locally, regionally and
    nationally. Fact sheets and trial summaries will be developed to provide accessible information
    to producers. The proposed study will engage WSU volunteers in surveying Agriotes spp.
    distribution. Utilizing this network has potential to expand the societal benefit of the proposed
    research beyond commercial production to the greater community-based food system.

    Project objectives from proposal:

    Objective 1. Evaluate wheat as a trap crop for control of Agriotes spp. in transplanted head lettuce production.
    Objective 2. Conduct a survey of Agriotes spp. distribution across Washington State.

    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.