Spotted Wing Drosophila: What We Learned In 2011

Growers in Pennsylvania have been on high alert ever since the spotted wing drosophila (SWD) was detected this past year. The most recent issue of Penn State University’s “Fruit Times” newsletter offers a refresher on the current SWD situation.

“Though many of us expected to find spotted wing drosophila in Pennsylvania in 2011, the widespread occurrence and sheer numbers found during the fall in some locations were surprising. Because of high SWD infestations, some growers gave up on harvesting fall raspberries and day-neutral strawberries. The problem was probably made worse by drenching rains from Hurricanes Irene and Lee which ruined berries that were then left in the field. SWD and other vinegar flies multiplied in the unharvested fruit, which then resulted in more SWD to infest ripening fruit that otherwise could have been harvested later. Fortunately, SWD populations were relatively low this year until fall. The concern for next year is that we don’t yet know how well SWD will survive the winter here, so we don’t know how many will be present at the beginning of the growing season next spring.”

To read the full report, click here.