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Creating a management system for spotted wing drosophila in caneberries and strawberries

The Issue

In September of 2008, UCCE in Santa Cruz County discovered a new vinegar fly pest infesting caneberries and strawberries, which was later described by the California Department of Food and Agriculture as Drosophila suzukii, and given the common name spotted wing drosophila. In 2009, spotted wing drosophila spread to cherries, blueberries, caneberries and strawberries in California, Oregon, Washington, British Columbia and Florida.

What Has ANR Done?

In collaboration with a private industry researcher, UCCE farm advisor Mark Bolda undertook an aggressive research program which sought to create a program of management for this new pest. Trapping media for monitoring were tested, pesticide controls both for conventional and organic systems were screened and the removal of cull fruit from the field to limit spotted wing drosophila population growth was put into practice. Once sufficiently usable information on these management procedures was established, the scientists established a program to share the information with growers, culminating with a standing-room-only event held at the Santa Cruz County UCCE office in early August 2009. The use of the Internet was critical in extending information on spotted wing drosophila to areas outside of Bolda’s assigned tri-county region. Thanks to the production of a blog facilitated by UC ANR Communication Services, growers and other professionals in Southern California, Oregon, Washington and British Columbia were immediately able to access updates posted on the blog about this pest.

The Payoff

Massive losses to spotted wing drosophila avoided through UCCE research and extension

California caneberry growers, who were among the most affected by spotted wing drosophila, quickly deployed the methods as outlined by UC Cooperative Extension and private industry partners. Yeast sugar water traps were placed in fields to monitor the magnitude of infestation. Effective pesticide sprays were made and many growers removed cull fruit from the field. The result was a drop in the amount of spotted wing drosophila infested fruit of at least 20 percent, resulting in a probable savings of $36 million to the industry.


Supporting Unit: Santa Cruz County

Mark Bolda, mpbolda@ucdavis.edu, (831) 763-8025