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Grower Survey on SWD

Please complete this national SWD survey, as soon as possible. Here’s the link to the Sustainable SWD Management survey.

The national Sustainable Spotted Wing Drosophila Management for United States Fruit Crops project funded by the USDA Specialty Crops Research Initiative needs and will benefit from feedback from growers across the country.

For those reading who aren’t growers, please:
1. Share the survey link at grower meetings this winter.
2. Share the survey link via social media.
3. Send the survey link to your grower email lists.

Thank you for helping out by taking this survey!  The goal is to measure the effects of SWD on fruit crop production. Results will be used to develop national research and extension projects to minimize future impacts of SWD. These may include:

  • Development of new management tactics and programs
  • Supporting new or expanded pesticide registrations for SWD
  • Development of educational material on SWD for growers, extension agents, and others

Individual survey responses are confidential and will never be shared. Participation is voluntary. No personally identifying information is collected. The survey should be completed by the person (age 18 or older) who is responsible for making pest management decisions on the berry farm.

Data may be summarized by state, crop, farm size, or farm type. Summaries of aggregated survey data will be publicly available on our project website, and will also be available by request. If you have questions about the survey, please contact Hannah Burrack at or Jean-Jacques Dubois at, North Carolina State University.

Funding for this project, Sustainable Spotted Wing Drosophila Management for US Fruit Crops, was provided by the National Institute of Food and Agriculture, U.S. Department of Agriculture Specialty Crops Research Initiative under Agreement No. 2015-51181-24252.

Workshops on Protected Culture

Are you looking for ways to protect your crop and lengthen your berry growing season? Plan to attend a Protected Culture Workshop for Berry Growers!  Two workshops will be held. The first in Portland, NY on February 28th at the Cornell Lake Erie Research and Extension Lab (CLEREL). The second in Riverhead, NY on March 7th at the Cornell Cooperative Extension Suffolk County Education Center.

The Protected Culture Workshops will feature hands-on activities and the newest research on tunnels and exclusion netting. New techniques for you to grow berries under cover will be shared.

Here’s what one berry grower said about protected culture …“I was able to supply my CSA members with strawberries right through the end of October!”

Plan now to attend! 
The Portland registration web page is: The registration deadline for Portland is February 24th.

The Riverhead registration web page is:  The registration deadline for Riverhead is March 3rd.

Workshop registration is $25 per person for NYS Berry Growers Association Members, and $50 per person for Non-Members. Registration includes lunch and take-home materials.

The Protected Culture Workshops will be packed with information:

  • strawberry cultivars for low tunnels
  • choosing and recycling tunnel plastic
  • using tools to predict weather events
  • disease and insect management
  • growing raspberries in high tunnels
  • using exclusion netting to protect against SWD
  • hands-on activities
  • a take-home resource guide and supplies

NYSBGA Protected Culture Workshop specifics:
DEC Credits in categories 1a, 10 and 22 are available.
Review the agenda via this link.

Tuesday, February 28, 2017
8:30 AM – 4:00 PM, lunch included
CLEREL (Cornell Lake Erie Research and Extension Lab)
6592 West Main Road, Portland, NY, 14769
Register by Friday, February 24th
For local information contact Kate Robinson,, 716-792-2800

Tuesday, March 7, 2017
8:30 AM – 4:00 PM, lunch included
Cornell Cooperative Extension Suffolk County Extension Education Center
423 Griffing Avenue, Suite 100, Riverhead, New York 11901-3071
Register by Friday, March 3rd
For local information contact Sandy Menasha,, 631-727-7850

Sponsored by the New York State Berry Growers Association, Cornell Cooperative Extension, and the Cornell University College of Agriculture and Life Sciences.

Webinar on SWD insecticidal control – today!

The SWD SCRI project is hosting a webinar today,  Jan. 25, 2017, at 12-1 p.m., with focus on insecticide control. To register for the webinar, visit the link below.

Members of the Sustainable Spotted Wing Drosophila Project will present an online webinar Jan. 25, 2017, at 12-1 p.m., highlighting information about controlling the invasive insect pest, spotted wing Drosophila (SWD). The webinar, “Making the Most of Your Insecticide Toolbox to Manage SWD,” will cover research conducted during the first year of this project, and will provide recommendations for growers to prepare for the 2017 growing season. This webinar will include time for questions from attendees.

Presenters from North Carolina State University, Michigan State University and the University of Georgia will report on their research on insecticidal control of SWD, with future webinars planned to report on monitoring, biological control and other aspects of this multistate project. Funded by the USDA Specialty Crops Research Initiative, this multiyear project aims to improve growers’ options for controlling this invasive pest.

To register online for this free webinar, go to “Making the Most of Your Insecticide Toolbox to Manage SWD.” Registered attendees will receive a link afterward to the slides and a recording of the webinar.

December 14 workshop postponed

Wednesday’s ‘Growing berries under cover workshop’ at the Cornell Lake Erie Research and Extension Lab, Portland, NY has been postponed until February 28.

You still have three chances to attend this program around New York State:

January 17, 2017: Oncenter Convention Center Syracuse, NY at the Empire State Producers EXPO to attend this workshop, register at

February 28, 2017: CLEREL (Cornell Lake Erie Research and Extension Lab) 6592 West Main Road Portland, NY, 14769 Register by February 21.

March 7, 2017: Cornell Cooperative Extension Suffolk County Extension Education Center 423 Griffing Avenue, Suite 100 Riverhead, New York 11901-3071 Register by Feb 28th

Visit the New York Berry Growers Association website for more information.

Contributed by Craig Cramer, Communications Specialist in the School of Integrative Plant Science, College of Agriculture and Life Sciences, Cornell University.

High tunnels, low tunnels, protected culture – Workshops!

Protected Culture WORKSHOPS for Berry Growers!  Three workshops will be held—in Portland, NY on December 14th; in Syracuse, NY on January 17; and in Riverhead, NY on March 7. Yes, we’re spreading the word on protected culture – high tunnels, low tunnels, and everything in between – with these workshops in Western NY, Central NY, and Long Island.

As dramatic weather events increase, pest pressure intensifies, and local markets vitalize, New York berry growers need ways to protect their crop and lengthen their season. Growers, educators and researchers are testing techniques for growing berries under cover and the current state of knowledge on protected culture will be shared with those attending these Workshops sponsored by the New York State Berry Growers Association (NYSBGA).

Plan now to attend one of these three regional workshops to learn more about these innovations in berry growing. These day-long workshops will feature multiple short presentations, hands-on activities, and reports from researchers, educators, and growers. Many New York State growers who are experimenting with growing under cover are having great successes and want to share those with you!  Just one testimonial on the benefits of protected culture …I was able to supply my CSA members with strawberries right through the end of October.

Register soon! Registration for the Protected Culture Workshops is open! Download the NYSBGA Workshop Registration Form ( Registration Form.pdf) from the NYSBGA website, fill it out and return it ASAP—don’t miss out on the Western NY workshop, which is December 14th!  Workshop registration is $25 per person for NYSBGA Members, and $50 per person for Non-Members, which includes lunch and take-home materials.

The Portland, NY Workshop Program is packed with information, as the other two workshops will be, as well:

  • strawberry cultivars for low tunnels
  • choosing and recycling tunnel plastic
  • using tools to predict weather events
  • disease and insect management
  • growing raspberries in high tunnels
  • using exclusion netting to protect against SWD
  • hands-on activities
  • a take-home resource guide and supplies

Look for DEC pesticide applicator re-certification credits in categories 1A, 22, 23 and 10.

Participants can save on workshop registration by joining the NYSBGA. 2017 Membership is $125 and applies to two individuals per farm.  Associate Membership is $75 for non-profit agricultural professionals. Business members can join for $250 and receive two advertisements in the NYSBGA newsletter, which reaches berry growers throughout the state and online.

NYSBGA Workshop dates and locations:

December 14, 2016:
CLEREL (Cornell Lake Erie Research and Extension Lab)
6592 West Main Road, Portland, NY, 14769
Register by December 7th

January 17, 2017:
Oncenter Convention Center Syracuse, NY during the EXPO
Register for this workshop via the Empire State Producers EXPO at

March 7, 2017:
Cornell Cooperative Extension Suffolk County Extension Education Center
423 Griffing Avenue, Suite 100, Riverhead, New York 11901-3071
Register by February 28th

The workshops are sponsored by the NYS Berry Growers Association, Cornell Cooperative Extension, Cornell University College of Agriculture and Life Sciences, with funding support from the NYS Legislature.

For more Workshop details visit:
Contact: Cara Fraver, NYSBGA
(646) 284-7762

SWD IPM Working Group – Oct 20-21

The 2016 NE IPM SWD Working Group meeting will happen on Friday, October 21st, 2016. We invite members of the NE IPM SWD Working Group and interested berry growers, educators, and consultants to participate. The Working Group meeting will be held at the NYSAES, Cornell University campus in Geneva, NY. 

If you are interested in attending, please contact Laura McDermott,, to register before Tuesday, October 18th.

As in years’ past, we will convene at 7:00pm the evening before (10/20) for dinner and conversation, then roll up our sleeves for a full day of research presentations, priority setting and discussion on Friday, 10/21.

Our objectives, listed below, will be reflected in a different meeting style this year. New this year: grower discussion panel, SWD research posters, SWD resources, break-out groups to review and rank SWD priorities, and updates from two national research projects on SWD.

Objective 1. Increased Networking among individuals and/or groups on SWD IPM.
Objective 2. Setting priorities for SWD IPM.
Objective 3. Develop Resources for SWD IPM.
Objective 4. Share Resources on SWD IPM.

On Friday’s agenda, October 21—

8:00am Welcome, Susan Brown, Director, NY State Agricultural Experiment Station

8:15amIntroduction, background and purpose, Juliet Carroll, Cornell University

8:25amDiscussion of Fruit Industry Impacts with Grower Panel

  • Dale Ila Riggs, The Berry Patch, NY
  • Nate Nourse, Nourse Farms, MA
  • TBD, Atlantic Blueberry Co., NJ
  • Brian Reeves, Reeves Farm, NY
  • Rick Reisinger & Lisa Brower, Rick’s Apple Country, NY

9:25amExtension Priorities, break-out groups

10:30am – Stop SWD website development, Cesar Rodriguez-Saona, Rutgers University

10:40amInsecticide registration, organic products, and MRL’s addressed by the IR4 Program, Krista Coleman, Program Assistant, Organic Support, IR4

11:00amRegulatory & Education Priorities, breakout groups

11:40amSWD Poster & Resources session 

12:00pm – Lunch, provided.  

1:00pm 2016 Status of SWD – Regional reports discussion, Laura McDermott, Cornell Cooperative Extension

1:35pmOverview of the National SWD SCRI project, Cesar Rodriguez-Saona, Rutgers University

1:50pmOverview of the Organic OREI project, Greg Loeb, Cornell University

2:05pm Research Priorities, break-out groups

2:45pmIPM Guidelines for SWD (15 min)

  • Year 1 – Brambles, Greg Loeb
  • Year 2 – Blueberry, Cesar Rodriguez-Saona

3:00pmSWD Working Group evaluation & thoughts for future, Laura McDermott and Juliet Carroll


Thank you for your continued interest in the research on and management of SWD.

Best regards from the SWD IPM Working Group committee,

SWD and sour rot of grapes

SWD populations are building up and the warm, humid weather of late summer and early fall is very favorable for spotted wing. Any fruit hanging will be at risk of infestation. Not until late November will the majority of female SWD no longer carry eggs, as they prepare for overwintering.

Wayne Wilcox, grape pathologist, Plant Pathology & Plant-Microbe Biology Section, Cornell University, sent this alert out, “…the warm, humid conditions are ideal for the yeast and bacteria that cause sour rot, not just for SWD. These weather conditions strongly favor sour rot, since sour rot appears to require three components: (1) yeast, (2) bacteria, and (3) fruit flies—either the “everyday” fruit fly Drosophila melanogaster or SWD Drosophila suzukii. SWD is NOT required for sour rot to occur and, indeed, we do not typically find it associated with sour rot in the Finger Lakes region, although sour rot can be common here.

Recent research information on grape sour rot from Wayne’s program was summarized last spring on pages 47-57 in GRAPE DISEASE CONTROL, 2016. Included in these pages are details on research trials in field and lab, management tactics, efficacy of fungicides and insecticides, and impact of training systems on the development of sour rot in wine grapes. For those of you growing wine grapes, advising growers on sour rot, or simply interested in a complex and difficult to control disease, these pages are definitely worth a read.

An interesting observation came in yesterday from a wine grape grower in the Finger Lakes where the region has been plagued by drought. Several inches of rain had fallen in their area recently, causing many berries in the cluster to swell and crack. This is an ideal setting for infestation by SWD, other Drosophila species, and fruit rot pathogens.

Herkimer County finds SWD

On August 20th, traps being monitored by Bernie Armata, Extension Educator, Herkimer County Cornell Cooperative Extension, caught 5 male SWD. These traps were in a blueberry planting and shortly after receiving the trap catch news, the grower did salt flotation on a fruit sample, confirmed larval presence and shut down harvest.

Two male SWD on a blueberry, photographed in early September 2013. SWD populations typically build to very high levels in late summer and early autumn.

Two male SWD on a blueberry, photographed in early September 2013. SWD populations typically build to very high levels in late summer and early autumn.

The good news is the grower was able to harvest 90% of their blueberry crop before SWD arrival.

Bernie adds that, “It would seem that SWD arrive in Central NY a bit later than some other areas of the state, as this has been the case two out of the last five or six years.”

SWD populations are building up. Any fruit hanging will be at risk of infestation. Not until late November will the majority of female SWD no longer carry eggs, to prepare for overwintering. If you have fruit in protected culture (high tunnels), be especially vigilant. SWD management during late summer and early fall must include insecticides to protect fruit from infestation, unless effective exclusion netting is being used.

2016 Trap Network Wrap-up

All SWD trapping locations have caught SWD. First trap catch occurred over a nine- to ten-week-long period, from June 8 to August 13. SWD was caught earlier this year than in prior years, but the hot and extremely dry weather across New York State appears to have benefited berry crops, which suffered lower infestation rates in July than might have been expected from the early arrival of SWD.

Distribution map for SWD, as determined by the SWD network operated by 25 Cornell University and Cornell Cooperative Extension scientists in 25 Counties, monitoring 117 traps.

Distribution map for SWD, with data contributed by the SWD network operated by 25 Cornell University and Cornell Cooperative Extension scientists in 25 Counties, monitoring 117 traps.

Twenty-five scientists monitored traps in 25 Counties this year. A total of 117 Scentry traps were deployed in the network, primarily in raspberry (summer and fall) and blueberry. The first trap network site to report SWD trap catch was in Suffolk County, Long Island. At about the same time, SWD was caught at a research location in the Finger Lakes region.

Although SWD might show up around the same time each year in a particular location, this doesn’t often hold true. For instance, the location in 2015 at which my program caught SWD first was among the last of our monitoring locations to catch SWD this year.

The long length of time, 66 days, over which first trap catch reports came in from across NY in 2016 and in prior years (56 days in 2015, 56 days in 2014, 76 days in 2013) provides evidence that SWD arrival across NY isn’t synchronous. For this reason, in addition to trap catch reports, growers should consider crop maturity and crop susceptibility to infestation when formulating management decisions.

With most of NY in the grips of a drought – abnormally dry, moderate drought, severe drought, and extreme drought as of August 25 – this could keep SWD population growth in check. The US drought outlook shows likely drought removal in the Hudson Valley region, but drought will likely persist in western NY and Suffolk County.

It is easy and fast to check fruit for SWD infestation. Leaky fruit and dull sunken areas on fruit point to infestation. A quick salt flotation assay provides a good measure of SWD infestation in fruit—time well spent. Consult the Cornell Fruit Resources SWD pages for more information on dealing with this invasive pest.

Updates from Global SWD Research

Spotted wing drosophila (SWD) is native to South East Asia. It was first recorded as an invasive species in Hawaii in 1980, and in both California and parts of Europe in 2008. Since then it has spread rapidly throughout temperate North America and Europe, mainly due to global trade combined with an initial lack of regulatory controls. Its annual rate of range expansion has recently been estimated at approx. 1000 km (~620 miles) per year, and it is now established in parts of South America and the Middle East.

As a result of its global economic impact, spotted wing drosophila is the target of an intense global research effort encompassing various aspects of its biology and control. This article summarizes the results of some of this recent research that offers potential for the development of future pest management strategies. Please note that these reports do not constitute recommendations at this stage.

Summary of life-cycle

Spotted wing drosophila overwinters as a specialized (darker) adult morph that has greater cold tolerance than the summer form. Overwintered flies emerge in spring and feed on nectar from early flowering weeds and crops. Overwintering adults may live for more than 200 days, but the longevity of the summer form is considerably less. Reproductively mature female flies lay eggs in the ripening fruits of a wide range of host plants, including many wild, uncultivated species. Each female may produce 100–400 eggs, laying approximately 20 per day (depending on host availability and environmental conditions).

Recent research from Italy has shown that spotted wing drosophila can complete its lifecycle at temperatures as low as 53 °F; however, adult activity is highest at temperatures between 68 and 77 °F, and is reduced at temperatures above 86 °F. Adults are most active at dawn and dusk.

Larvae develop inside the fruit and complete their development in 3-13 days (depending on temperature). Pupation can occur in the fruit or in the soil, and the entire life-cycle can be completed in approx. 7–10 days (again, depending on temperature). Under optimal conditions, up to 13 generations per year are possible, although in the US and Canada 3–9 generations are more typical. Canadian research suggests that the lower lethal temperature for adult flies is in the region of 19 °F, although cold tolerance depends on the extent of prior exposure to fluctuating cool temperatures. There is evidence to suggest that females are more cold-tolerant than males.

Recent research results

i. Host plants

Fruits of susceptible host plants are liable to attack as soon as the fruit begins to soften and show color. Research with both raspberries and blueberries has shown that green, hard fruits are not at risk. The likelihood of egg-laying increases as the force needed to penetrate the fruit decreases: hence egg-laying is consistently high in raspberry and other thin-skinned fruits. In a recent US study, calcium treatments applied to blueberries in a field experiment produced firmer fruits that harbored fewer SWD eggs than fruits from untreated plots.

The wide host plant range of spotted wing drosophila can influence population levels at the landscape scale. In one US study, the abundance of wild hosts in nearby woods and hedgerows was implicated in the increased early-season risk of spotted wing drosophila in adjacent raspberries. However, it did not appear to influence the subsequent rate of population development in those crops.

As an indication of the wide host plant range of spotted wing drosophila, in recent field surveys in Europe, more than 24,000 adult flies successfully emerged from the fruits of 84 plant species from 19 different plant families, 38 of which were non-native species. The highest infestations were found in species of Cornus (dogwoods), Prunus (relatives of stone fruits such as cherries, plums, etc.), Rubus (raspberries, blackberries, and relatives), Sambucus (elderberry) and Vaccinium (blueberries and relatives). US research has shown a similarly wide range of hosts, including many of the above, as well as Morus (mulberry), edible blue honeysuckle (also known as haskap or honeyberry), and some common herbaceous weeds such as Solanum dulcamara (bittersweet nightshade). In Europe, spotted wing drosophila has also been found infesting mistletoe berries (Viscum album) – probably one of the earliest host fruits available for spring egg-laying.

In another European study, the fruits of several plants stimulated egg-laying by SWD females, but did not support full larval development and successful adult emergence. If these lab reports are supported by future field studies, such plants might be a useful component of an integrated control strategy as trap plants or so-called ‘dead-end’ hosts. For such an approach to be successful, however, the fruits must either be significantly more attractive than the crop being protected, or be present either earlier or later than the fruits of the target crop.

ii. Interactions with yeast

Once mated, adult female spotted wing drosophila respond strongly to odors produced by wild yeast species associated with fruit. These yeast odors are used as feeding cues, and may form the basis for developing an “attract-and-kill” strategy: in recent research, exposing flies to a mixture of yeast and insecticide reduced egg-laying and increased the mortality of adult flies compared to insecticide treatments alone. However, related work has shown that the effect is dependent on both the insecticide used, and the species of yeast. In some cases, there was no additional benefit from adding yeast to an insecticide spray that was also supplemented with cane sugar.

A rather more advanced approach to exploiting the attraction of SWD to yeasts involves the use of a genetically modified yeast strain to disrupt the expression and regulation of some of the pest’s critical genes by interfering with the normal functioning of its ribonucleic acid (RNA). Such ‘RNA interference’ techniques (RNAi) are being developed for many important crop pests. Recent lab-based research in California involved feeding a genetically modified yeast strain to adult spotted wing drosophila and recording mortality, activity and post-treatment egg-production: while there was no increase in fly mortality as a result of the treatment, the flies were less active and laid fewer eggs, prompting speculation that further refinements of the technique might have a future role in pest management.

iii. Environmental factors

Previous research has shown that SWD trap catches decline when humidity is low. Several research groups are now investigating whether different pruning and irrigation practices can reduce within-crop temperature and humidity and hence slow the rate of SWD population increase. Other research groups are comparing the survival of SWD in blueberry plantings with or without black plastic weed mats: the higher temperatures associated with the mats may reduce the survival of pupae in infested fruit that falls to the ground.

iv. Biological control

Various research groups in both North America and Europe have addressed the possible impact on spotted wing drosophila of both native natural enemies and a range of commercially available predators, parasitic nematodes and fungal pathogens. However, many of the studies have been conducted only under laboratory conditions and the results have been rather variable.

Two species of parasitic wasps (parasitoids) (Trichopria drosophilae and Pachycrepoideus vindemiae) have been found attacking SWD pupae in both the USA and Europe, as well as in the pest’s native range (various parts of Asia, including Japan and Korea). Trichopria drosophilae has a narrower host range than P. vindemiae and may have potential for mass-rearing for use in augmentative release programs. Additional parasitoids collected from South Korea are currently undergoing evaluation under quarantine in California, but it will be some time before such tests are completed.

v. Chemical control

At present, commercial producers rely heavily on season-long applications of a rather limited range of insecticides for spotted wing drosophila. With a pest such as this, with rapid rates of development and multiple generations per year, the risk of selecting for insecticide resistance is high. This is particularly true for enclosed tunnel systems (because of limited fly movement) and in organic plantings, where there are few effective chemical control options. There is already some evidence of reduced susceptibility to spinosad (Entrust®) in some organically managed berries in the western US. On the other hand, a recent study in Canada showed no increase in resistance to malathion in a laboratory population of SWD exposed to sub-lethal concentrations for 30 generations. Baseline monitoring for resistance to the most widely used insecticides is currently being conducted in fruit-producing regions in various parts of the US. Such monitoring will provide a valuable early-warning system if and when resistance develops.

In the meantime, a recent report from Georgia on the efficacy of insecticides used for SWD in blueberries showed that the adjuvant Nu Film P had some effect on prolonging the activity of spinetoram and spinosad after a simulated rainfall equivalent to 0.5″, and of malathion after a rainfall of approx. 1″. Nu Film P is listed by the Organic Materials Review Institute (OMRI) as suitable for use in organic production.

Future prospects

In conclusion, the heavy investment in research on spotted wing drosophila is now starting to produce results that at the very least will provide some additional management tools, and which in future may form the basis of a multi-tactic, integrated approach to the management of this pest.

This article was contributed by Tess Grasswitz, Extension Associate, Lake Ontario Fruit Program, Cornell Cooperative Extension. Originally published in Fruit Notes, Vol 16, Issue 18, August 18, 2016.

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