Spotted Wing Drosophila
Welcome to MSU’s Spotted Wing Drosophila site
This site contains information and links for growers and homeowners about a new invasive pest in Michigan, the Spotted Wing Drosophila.
For weekly reports on the status of this pest, stay informed through MSU Extension’s Fruit & Nuts News.
Weekly Michigan spotted wing Drosophila reports:
- Aug. 27, 2013 - As harvest is winding down in many crops at high risk from spotted wing Drosophila, fly numbers are similar to last week’s total catch.
- Aug. 20, 2013 - Spotted wing Drosophila captures continue to rise as harvest winds down in some blueberry and raspberry sites.
- Aug. 13, 2013 - Spotted wing Drosophila catches are increasing in fields and orchards where harvest is completed and insecticide residues are minimal.
- Aug. 6, 2013 - Spotted wing Drosophila continues to be captured throughout Michigan, and larvae have been detected in multiple crops, so protect susceptible fruit.
- July 30, 2013 - Sharp increase in spotted wing drosophila captures in the past week in southern Michigan counties, and first detection of infestation in unsprayed cherries.
- July 23, 2013 - Spotted wing Drosophila fly captures are increasing sharply at some sites. Some still have no catch, and first spotted wing Drosophila catch is reported in northwest Michigan.
- July 16, 2013 - Spotted wing Drosophila catches increase slightly in southwest Michigan.
- July 9, 2013 - Spotted wing Drosophila catches remain low throughout Michigan with catches in small fruits and tart cherries.
- July 2, 2013 - New spotted wing Drosophila detections have been made in Berrien, Allegan and Ottawa counties in southwest and west central Michigan.
- June 25, 2013 - Two more spotted wing Drosophila were caught in southwest Michigan: one in raspberry high tunnels and a second adjacent to blueberries.
- June 18, 2013 – First catches of spotted wing Drosophila indicate low activity. Weekly reports to continue.
Some key articles from MSU Extension News:
- 2014 statewide trapping system crucial for spotted wing Drosophila and brown marmorated stink bug (Jan. 14, 2014)
- What are we learning about spotted wing Drosophila management in berries this season? (Aug. 26, 2013)
- Michigan berry growers face a challenging time managing spotted wing Drosophila (Aug. 16, 2013)
- Updated spotted wing Drosophila management guidelines in Michigan raspberries and blackberries (July 30, 2013)
- Increasing spotted wing Drosophila activity highlights need for berry fruit protection (July 23, 2013)
- Recent spotted wing Drosophila catches indicate ripening berries should be protected (July 2, 2013)
- First capture of spotted wing Drosophila in Michigan for 2013 (June 11, 2013)
- Spotted wing Drosophila monitoring should be started soon - know what to look for (June 4, 2013)
- Spotted wing Drosophila management and control tools for small fruit growers (April 25, 2013)
- Special Local Needs label approved for Malathion in blueberries to control spotted wing Drosophila (April 2, 2013)
The Spotted Wing Drosophila (SWD) is a vinegar fly of East Asian origin that can cause damage to many fruit crops. This small insect has been in Hawaii since the 1980s, was detected in California in 2008, spread through the West Coast in 2009, and was detected in Florida, Utah, the Carolinas, Wisconsin and Michigan for the first time in 2010. Because the flies are only a few millimeters long and cannot fly very far, natural dispersion between states is unlikely. Human-assisted transportation is a more likely cause of the recent rapid spread. It appears that this insect has become widely established through North America.
What crops are affected?
SWD has been detected in traps located near berry crops, grapes, cherries and other tree fruits. The flies have a preference for softer-fleshed fruit.
Status in Michigan
In fall 2010, SWD was detected in Michigan for the first time as part of a widespread Early Detection and Rapid Response program. SWD flies have now been detected in 22 counties in the southern peninsula of Michigan. Activity period spans from June through to late fall.
What is being done?
A SWD Response Team has been formed that combines the expertise of MSU entomologists, horticulturalists, Extension educators, and Michigan Department of Agriculture staff. This website will be the central location for dissemination of information about this insect. Check back for updates. This team is also helping to coordinate research projects to understand how best to protect fruit from infestation by this new pest.
We are confident that the Integrated Pest Management (IPM) programs available for SWD control can be implemented to enable continued harvest of high-quality crops. See our fact sheets for English and Spanish information on monitoring for this pest, and recommendations for management in blueberry (last updated June 2012).
1) MSU Fact sheet, available in English and Spanish.
2) MSU‘s guide to identifying spotted wing Drosophila and separating them from other species caught in traps.
4) SWD Information from Oregon State University
5) Past articles from MSU Extension’s Fruit & Nut News:
- End of season spotted wing Drosophila management in raspberries (Oct. 29, 2012)
- Fall-harvesting berry growers need to monitor and manage SWD (Sept. 4, 2012)
- Post-harvest spraying for SWD pros, cons, and a list of issues (Aug. 22, 2012)
- Trapping, fruit sampling and fruit protection methods (July 2, 2012)
- SWD detections are increasing in fruit crops (June 19, 2012)
- Monitoring for SWD to detect early activity (May 29, 2012)
Funding for the SWD Response Team
The SWD Response Team is funded by Project GREEEN, the Michigan Department of Agriculture and Rural Development, and USDA.