The first adult spotted wing Drosophila (SWD) fly of the 2015 growing season was detected in a trap collected on June 23, 2015, in Rosemount, MN (Dakota Co.). Based on this detection, home gardeners with soft-skinned fruit such as June bearing strawberries, summer bearing (floricane) raspberries, and blueberries should begin monitoring their fields, if they haven’t already.
Most June bearing strawberries in Minnesota should be nearing the end of fruiting but summer bearing raspberries and most blueberry varieties should have green fruit and potentially low levels of ripening fruit. Fall bearing (primocane) raspberries and blackberries should not be flowering yet, but these crops will be at increased risk later in the season as the populations of SWD should continue to increase.
|Spotted wing Drosophila attacks many types of soft-skinned |
fruit, including raspberries, blueberries, and strawberries.
Photo: Jeffrey Hahn, UMN Extension
SWD flies resemble common fruit flies found near overripe fruit, but unlike the common fruit fly, female SWD have the potential to damage otherwise healthy, intact fruit. They will also exploit fruit that has previous damage such as splitting or wounds from birds or disease.
Home gardeners with susceptible fruit are encouraged to monitor their fields regularly to confirm the presence of SWD before considering chemical management options. Although cultural management options are limited, they have been shown to help minimize rapid buildup of SWD populations.
The Department of Entomology and the UMN Extension-IPM Program, in collaboration with the MDA, are monitoring multiple farm locations in the greater metro area and will be posting regular updates regarding SWD phenology and activity on the UMN FruitEdge website.
For more information, see Spotted wing Drosophila in home gardens.