More on Spotted Wing Drosophila (SWD) ... be watchful of high tunnel raspberries and strawberries

From the latest issue of the Illinois Fruit and Vegetable News:

Spotted wing Drosophila occurrence in IL, based on adult specimens.

 Previous issues of this newsletter have included reports on spotted wing Drosophila (SWD) ... see http://ipm.illinois.edu/ifvn/contents.php?id=11#fruit and http://ipm.illinois.edu/ifvn/contents.php?id=13#fruit.  The map indicates the counties in which the presence of SWD has been confirmed, and in several of these cases, larval infestations of raspberries have been reported as well.  As I stated earlier, I suspect that SWD is present in most if not all Illinois counties and that counties not marked on the map below represent areas where we have not monitored enough to detect it yet.

As fall brings frost and freezes to the area, outdoor production of raspberries will end, and so will reports of outdoor infestations of fruit.  Be aware, however, that this insect has been recorded from high-tunnel raspberries and strawberries.  As production of these crops continues in high tunnels, monitoring for SWD will be essential.  Michigan State University's web site on SWD includes directions on how to construct traps to monitor for it ... see http://www.ipm.msu.edu/SWD/SWD-monitor.htm.

Issue 13 of this newsletter listed effective insecticides for SWD control in raspberries.  For strawberries, labeled insecticides that should reduce damage from this insect include Brigadier (7-day PHI; residual activity of about 7 days), Danitol (2-day PHI; residual activity of about 7 days), Entrust (1-day PHI, OMRI-approved; residual activity of about 3-5 days), Pyganic and other natural pyrethrins (0-day PHI, OMRI-approved; residual activity of about 1-2 days), Malathion (3-day PHI; residual activity of about 5 days), and Radiant (1-day PHI; residual activity of about 7 days).  (PHI = preharvest interval, the number of days that must elapse between final application and harvest; OMRI = Organic Materials Review Institute.)

Rick Weinzierl (217-244-2126; weinzier@illinois.edu)