Control of Western Tarnished Plant Bug (WTPB) Lygus hesperus Knight in Organic Strawberry Production Systems Using Trap Crops and Tractor-mounted Vacuums

Project Overview

Project Type: Research and Education
Funds awarded in 2002: $31,280.00
Projected End Date: 12/31/2004
Region: Western
State: California
Principal Investigator:
Dr. Sean Swezey
Center for Agroecology and Sustainable Food System


  • Fruits: berries (strawberries)


  • Crop Production: intercropping, strip tillage
  • Education and Training: demonstration, on-farm/ranch research
  • Farm Business Management: whole farm planning
  • Natural Resources/Environment: hedgerows
  • Pest Management: biological control, trap crops


    A twice-weekly summer vacuuming treatment of alfalfa trap crops significantly lowered damage due to WTPB in associated organic strawberries in June 2003 and June and July 2004 compared with the organic strawberry grower’s standard whole-field vacuuming treatment. This vacuumed alfalfa trap crop treatment reduces grower’s vacuuming costs (tractor, tractor fuel, and driver time) by 78%. An economic analysis indicates that positive returns from the use of trap crops were observed in June 2003 and June and July 2004, and the overall positive return for the three months of trap cropping treatments in 2004 was calculated at +$734/acre.

    Project objectives:

    Our specific objectives included:

    1) Establish and evaluate the attractiveness to WTPB of on-farm trap crop plantings in organic strawberry fields by planting, irrigating, weeding, and maintenance of replicated culinary radish and alfalfa on beds directly adjacent to commercial strawberry beds.
    2) Beginning in June of 2003, use tractor-mounted vacuum devices in a replicated experiment of alfalfa trap crops and organic strawberries including treatments that: a) vacuum only the trap crop vegetation, b) vacuum the whole strawberry field in the absence of the trap crop vegetation, c) leave trap crop vegetation and the field unvacuumed, and d) leave an untreated (unvacuumed) control without trap crop vegetation in 2003; or vacuum both the trap crop and the adjacent strawberries in 2004.
    3) Monitor the weekly summer densities of WTPB and associated natural enemies in strawberries and trap crops as a function of distance from the trap crop.
    4) Monitor seasonal damage caused to strawberry fruit as a function of treatment.
    5) Calculate the relative economic costs and benefits of the treatments of interest to the grower-cooperator.
    6) Partner with other experts in the field of on-farm habitat conservation and farmscaping to hold two extension/training workshops for extension of experimental results to coastal Central California agricultural professionals.

    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.