DEPARTMENTS


Plant Health




Spotted wing drosophila (Drosophila suzukii).
Photo by Hannah Burrack, North Carolina State University; Bugwood.org

Spotted wing drosophila spotted in Indiana

The first confirmed identification of spotted wing drosophila (SWD) in Indiana was reported in October; the pest was found on a raspberry sample from a home garden. The fruit fly, which hails from Asia, was found in Hawaii in the 1980s; since then it has migrated to California (confirmed in 2008) and has been widely reported in Western states, Florida, other East Coast states and in the Midwest. Berry crops, grapes, cherries and other tree fruit are at risk.

Why do you care? The past few years have seen a dramatic increase in the popularity of fruit- and vegetable-bearing plants, many of which have been incorporated into gardens otherwise designated as ornamental. If you grow, spec or sell fruit trees or shrubs that bear soft-fleshed fruit, such as raspberries and blueberries, these plants may be at risk.


Cane fruit are a favorite host of spotted wing drosophila.
Photo by Hannah Burrack, North Carolina State University; Bugwood.org

The tiny flies are only a couple of millimeters long, and because they're unable to fly very far, it's not likely that they're able to establish presence in a new area through natural dispersal. So it's commonly thought that spotted wing drosophila has been ferried from state to state by human-assisted transportation. And because these pests are so tiny, they're not always easy to detect. Traps baited with apple cider vinegar catch both males and females - as well as other wee beasties. A hand lens is a critical tool to aid in distinguishing spotted wing drosophila from other native vinegar flies: Look for a distinctive dark dot on the wings of males. Unfortunately, females don't bear the same marking, but a 30X magnification hand lens will help detect a saw-toothed ovipositor. Better yet, check with your local extension office.


Brown marmorated stink bug (Halyomorpha halys) recently has been confirmed in Iowa.
Photo by David R. Lance, USDA APHIS PPQ; Bugwood.org

Stink bug detected in Iowa

The brown marmorated stink bug (BMSB; Halyomorpha halys) has found a new home in Iowa. Scott County appears to be the site of established populations, with several sightings in Bettendorf and Davenport, the Scott County seat. The bug was first identified in the U.S. in Pennsylvania in 2001, and has spread rapidly to claim 38 states (see "Stink bug invades Maryland" by Stanton Gill, October 2010).

Fifth instar nymphs of Halyomorpha halys (brown marmorated stink bug) feed on foliage. A native species of stink bug, Acrosternum hilare (green stink bug) can be seen at the top, slightly hidden by the crowd.
Photo by David R. Lance, USDA APHIS PPQ; Bugwood.org

Detection is common in fall, when the stink bugs take advantage of warm days to migrate to overwintering sites. They tend to congregate - often in great numbers - on houses and buildings, often entering structures along with box elder bugs and Asian lady beetles. During the summer, stink bugs use their piercing-sucking mouthparts to feed on plant sap from fruits, vegetables, ornamentals and field crops.