SWD now Present in PA … (SWD Update, July 10, 2014)

Posted: July 11, 2014

Growers of raspberries (both red and black), blackberries, and blueberries in particular should be monitoring for spotted wing drosophila (check traps daily if possible), and should be prepared with effective materials for control.
Photo by A. Surcica.

Photo by A. Surcica.

Spotted wing drosophila (SWD) was found in very low numbers in traps in southeastern PA (3 males out of 40 traps using a new commercially-available SWD Lure – Trece, Inc). Two of the SWD were in an unharvested cherry block, and one was in a trap in black raspberries. No female SWD were found at these sites yet, but judging from our brief experience with this pest in PA, it won't be long.

An "at-a-glance" graph of a national efficacy ranking of insecticides for SWD control, developed by Rufus Isaacs at Michigan State, is posted in a recent issue of the Rutgers Blueberry Bulletin. When spraying, be sure to maximize coverage throughout the entire plant canopy, as a few missed SWD can rapidly re-infest the planting, and rotate among pesticide classes. SWD's multiple generations per year makes resistance development more likely than usual, and the only thing that we need less than SWD is pesticide-resistant SWD. Also utilize all cultural controls to minimize buildup of SWD populations, though cultural controls alone have not been enough to control this pest.

Information on all of these topics is available in the Penn State SWD fact sheets updated in 2013:

Part 1, Overview and Identification

Part 2, Natural History

Part 3, Monitoring

Part 4, Management

Current pesticide labels, including 24C (Special Local Needs for Malathion 8F) and 2(ee) labels for SWD can be obtained at Crop Data Management Systems by clicking on "Services" and then choosing "Labels/MSDS".

Comprehensive entomology updates are posted each Friday at the Penn State Fruit Research and Extension Center website.

Contact Information

Dave Biddinger
  • Tree Fruit Research Entomologist
Phone: 717-677-6116
Kathy Demchak
  • Senior Extension Associate
Phone: 814-863-2303