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

View the project final report

Commodities

• Vegetables: greens (lettuces)

Practices

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

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.

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.