Noncrop Host Plants of Spotted Wing Drosophila in North America

Spotted wing Drosophila (SWD), Drosophila suzukii, is an invasive fly that lays eggs in ripening and ripe berries and stone fruits. The developing larvae can make the fruit unmarketable, so this pest is a concern to producers, packers, processors, and distributors of these crops.

Landscapes surrounding fruit production fields often include hedgerows, adjacent field margins, and woody or riparian areas with ornamentals, unmanaged shrubs, vines, or other plants that also produce fruits. Noncrop habitats can meet the requirements that favor SWD adults and their natural enemies: food, shelter, shade, and humidity. In addition, many noncrop fruits can support developing larvae of SWD. As populations of SWD build in noncrop hosts, these areas can become “hot spots” from which SWD can move into fields as commercial fruits begin to ripen. In some regions, these plants are important for late season population buildup outside crop fields.

From this publication, commercial and backyard fruit growers and field advisors will learn which plants can serve as alternate egg-laying sites for SWD. This list of noncommercial fruits was developed from multiyear sampling to determine likely noncrop hosts for SWD larvae. Regional differences in the importance of each plant host may occur due to differences in environmental conditions. The list is not exhaustive but includes what is known at this time about plants commonly found in British Columbia, Washington, Oregon, California, Michigan, New York, and Florida. We expect this list to expand as more becomes known about noncrop hosts for SWD.

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