Lessons Learned From SWD In Michigan

Rufus IsaacsMichigan fruit researchers and growers have had several seasons of dealing with the potentially devastating consequences of spotted wing drosophila (SWD) arriving in the Great Lakes region. Rufus Isaacs, a professor of entomology at Michigan State University (MSU) reflects on the lessons learned along the way with a few years of controlling SWD under growers’ belts in Michigan.

Q: What have you learned about SWD so far?
Isaacs: It is clear that SWD is a challenging new insect pest for growers of susceptible crops, and that its management needs to be a priority for those growers to harvest high quality fruit.

Q: What type of habitats does SWD tend to favor?
Isaacs: SWD likes to be in the shade in more humid areas and it is able to persist on wild fruiting plants outside of crop fields. Because of this, we tend to find it in wild habitats a little earlier than in crop fields. These areas are refuges for SWD and so we also see the pest pressure is higher at field perimeters adjacent to these wild habitats.

Q: What type of spray coverage should growers consider to have the most control on SWD?
Isaacs: Because SWD prefers to be in shaded areas, it is important that sprays are penetrating into the plant canopy. A quick check with some water-sensitive paper can be useful for seeing whether your water volume and sprayer settings are getting the job done.

Q: What insecticides would you recommend for growers in control of SWD?
Isaacs: From our work in Michigan and the other research reports I have seen, the top-performing insecticides against SWD include Mustang Maxx, Danitol, Lannate, Delegate, Imidan, and Exirel. There are some others with good activity, but these six have the most consistent high rankings by fruit entomologists across the United States.

Q: What other steps should growers take in 2014 against SWD?
Isaacs: It is important to be monitoring for this pest. Using baited traps will allow a grower to determine when SWD becomes active on your own farm and where the hot spots are. Sampling the fruit for larvae using a simple salt solution (one cup of salt per gallon) can also help you know if your spray program is working and whether the fruit can be harvested. Where it is possible, more rapid harvesting can help reduce SWD infestation.

It is also clear that rapid chilling of fruit after harvest will stop further development of SWD, and so this can be used to help reduce declines in quality or larval detections in fruit. Pruning your crop well is another approach, because it reduces hiding places for SWD, plus it has the added benefit of helping get better spray penetration of the crop canopy.

Finally, small growers or those with hoop house structures installed already might be interested in using exclusion netting to keep SWD out of their plantings. This is something we are testing this summer in raspberry and blueberry.

Q: Is there a common mistake growers make when trying to manage SWD?
Isaacs: Don’t assume its not there because you haven’t had it before, and don’t assume that their programs for managing other fruit flies (e.g. blueberry maggot, cherry fruit fly) will work against SWD. This pest has caught some people by surprise because it is tiny and can go undetected until infestations are quite high. So, not monitoring, or thinking you don’t have it, has led to some problems with SWD at harvest time. Stretching spray intervals too long or waiting too late to start protecting the crop have also caused problems.

Q: What type of research is being conducted on SWD this season and moving forward?
Isaacs: There is so much! It seems that every fruit entomologist in North America and Europe who have an interest in berry, cherry, or grape crops is doing something to address this pest. Chemical, physical, cultural, genetic, molecular, and biological approaches are being studied from all angles. The recent publication of the SWD genome will facilitate whole new directions of research too.

Q: Will the cold winter affect the pressure growers see from SWD this year?
Isaacs: We don’t have enough seasons of experience to say. The super-cold winter of 2013-14 was also a snowy winter, and so overwintering flies would have been quite protected under that insulating later or up against buildings. So, I expect SWD to be back again in time for later summer fruit crops. I’m advising growers to be ready for it, and the monitoring will tell us whether the winter had an effect.

MSU Extension will be starting its weekly SWD reporting in June. Visit our website at IPM.MSU.edu/SWD.htm for management guides and for the weekly reports.

Q: How can growers help contribute to the research?
Isaacs: We have had great cooperation from growers allowing us access to their fields for our research. Maintaining support for the research stations, Cooperative Extension, and applied research programs at the land grant universities, and for the IR-4 program, will be essential for addressing this invasive pest — and the next one.

Topics: , , , ,

Leave a Reply

Berries Stories
Alto Straughn receives distinguished alumnus award from UF President Kent Fuchs
Berries
May 4, 2017
Florida Farming Pioneer Still Making the Honor Roll
Alto Straughn presented with University of Florida’s Distinguished Alumnus Award. Read More
Berries
May 2, 2017
Southeastern Strawberry Growers Advised to Prepare for Disease Pressure
Recent rain is conducive to the main strawberry fruit rot diseases, according to the chief of the Southern Region IPM Center. Read More
Berries
April 26, 2017
Tips To Manage Winter-Damaged Blueberries
While low-chill varieties in Southern states may have experienced freeze damage for the second year in a row, giving those plants extra care will help ensure a good start to the 2018 growing season. Read More
The Hill family of Southern Hill Farms in Florida
Berries
April 13, 2017
Florida Farming Family Staying on Top of the Blueberry Game
The Hill family of Southern Hill Farms continues to up their efforts to diversify business and stay out ahead of a competitive market. Read More
Berries
April 10, 2017
North Carolina Blueberry Crop Still Kicking
Thanks to pruning cuts and a diverse mix of cultivars, the majority of the crop survived a series of March freezes. Read More
Closeup of Florida blueberries
Berries
April 6, 2017
Study Shows Bumblebees Can Boost Blueberry Yield Big Time
UF/IFAS researchers find placing hives of the distinct pollinator in the field pumps up output by 70%. Read More
Berries
March 30, 2017
Chateau Herbicide SW Now Registered for Use in Citrus, Caneberries
Broad spectrum preemergent herbicide to control broadleaf and grasses. Read More
SWD On Raspberry
Berries
March 26, 2017
Outsmarting SWD with Social Media
Entomologist in Kentucky uses social media for pest updates, trap catches. Read More
Freeze protected blueberry bushes in Florida
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from Late-Season Cold Snap
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Frozen blueberries
Berries
March 15, 2017
Arctic Blast Gives Southern Fruit Growers the Chills
Peaches and berries in bloom most at risk from freezing temperatures. Read More
Growers boot up drone technology on the farm
Berries
March 3, 2017
Specialty Crops Primed for Precision Agriculture
Employing the latest horticultural technology tools could have substantial financial benefits for producers of hand-picked specialty crops, according to a new research paper. Read More
Berries
March 2, 2017
Pruning Pointers for Dormant Care of Berries
If you haven’t started pruning your berries, it’s time you do. Read More
Berries
February 26, 2017
Advantages to Growing Southern Highbush Blueberries
Growers in some regions where temperatures don’t get too low could consider the benefits of Southern highbush varieties. Read More
Berries
February 23, 2017
Primocane: A Major Innovation in Berry Production
I’ve witnessed the rise of primocane-fruiting blackberries, from first selections to integration in the market. Read More
2017 Florida Strawberry Picking Challenge winners
Berries
February 22, 2017
Florida Strawberry Picking Contest a Big Winner for Charity
Fourth-annual fundraising event brings in more than $100,000 to benefit children of local farmworkers. Read More
The Latest
Berries
May 26, 2017
Jury Sides with University in Strawberry…
Decision says former breeders infringed on UC patents to develop material for corporate breeding firm. Read More
Berries
May 23, 2017
Researchers Examining Potential for Long…
Team at Penn State University using low and high tunnels and plastic coverings to extend raspberry and strawberry seasons. Read More
Berries
May 15, 2017
Grower Comments on Pyrethroids Being Sou…
Comment period on popular class of insecticides opens today. Read More
Berries
May 4, 2017
Florida Farming Pioneer Still Making the…
Alto Straughn presented with University of Florida’s Distinguished Alumnus Award. Read More
Berries
May 2, 2017
Southeastern Strawberry Growers Advised …
Recent rain is conducive to the main strawberry fruit rot diseases, according to the chief of the Southern Region IPM Center. Read More
Berries
April 26, 2017
Tips To Manage Winter-Damaged Blueberrie…
While low-chill varieties in Southern states may have experienced freeze damage for the second year in a row, giving those plants extra care will help ensure a good start to the 2018 growing season. Read More
Berries
April 13, 2017
Florida Farming Family Staying on Top of…
The Hill family of Southern Hill Farms continues to up their efforts to diversify business and stay out ahead of a competitive market. Read More
Berries
April 10, 2017
North Carolina Blueberry Crop Still Kick…
Thanks to pruning cuts and a diverse mix of cultivars, the majority of the crop survived a series of March freezes. Read More
Berries
April 6, 2017
Study Shows Bumblebees Can Boost Blueber…
UF/IFAS researchers find placing hives of the distinct pollinator in the field pumps up output by 70%. Read More
Berries
March 30, 2017
Chateau Herbicide SW Now Registered for …
Broad spectrum preemergent herbicide to control broadleaf and grasses. Read More
Berries
March 26, 2017
Outsmarting SWD with Social Media
Entomologist in Kentucky uses social media for pest updates, trap catches. Read More
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from…
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Berries
March 15, 2017
Arctic Blast Gives Southern Fruit Grower…
Peaches and berries in bloom most at risk from freezing temperatures. Read More
Berries
March 3, 2017
Specialty Crops Primed for Precision Agr…
Employing the latest horticultural technology tools could have substantial financial benefits for producers of hand-picked specialty crops, according to a new research paper. Read More
Berries
March 2, 2017
Pruning Pointers for Dormant Care of Ber…
If you haven’t started pruning your berries, it’s time you do. Read More
Berries
February 26, 2017
Advantages to Growing Southern Highbush …
Growers in some regions where temperatures don’t get too low could consider the benefits of Southern highbush varieties. Read More
Berries
February 23, 2017
Primocane: A Major Innovation in Berry P…
I’ve witnessed the rise of primocane-fruiting blackberries, from first selections to integration in the market. Read More
Berries
February 22, 2017
Florida Strawberry Picking Contest a Big…
Fourth-annual fundraising event brings in more than $100,000 to benefit children of local farmworkers. Read More