The SWD monitoring network Counties are all positive for SWD as of last week, August 28, 2015. A lot of SWD are being caught in traps in research sites now with population numbers expected to climb into the thousands before frost knocks them back and forces them into winter diapause.
Reports are coming in of severely infested fall raspberries. This fall will be especially challenging for fall harvest of susceptible fruits. Blackberries and raspberries are particularly vulnerable and will require intensive management with sanitation and insecticide protection. One sanitation strategy used in California for berries is for workers to crush any fruit that has fallen to the ground, reducing the chance of larvae surviving to grow into egg-laying adults. For insecticides, maintaining good coverage is essential, so keep track of rain events that can wash off insecticide (>0.5 inch) and reapply at the appropriate interval listed on the labels.
Late-season blueberries, peaches, plums and grapes are vulnerable to infestation, though not as susceptible as brambles, it will be wise to examine the crop for infestation. Fruit that is softer than it should be, with dull sunken areas and tiny drops of sap may be infested. Hold marketable fruit samples on white paper towels for a day or so and rotate it to see if it is leaking from tiny pinholes indicative of larval breathing sites. Use salt floatation to float out larvae and assess the relative abundance of larval infestation and severity of the problem. Place 50 ripe, marketable fruit in a plastic bag, cover with salt solution (1 Tbsp salt/cup water) and examine in 15-30 minutes for emerging larvae. Larvae are small 1-3 mm or 1/16-2/16 inch long. More on checking fruit for infestation is in the blog Do my fruit have SWD?
If fruit is still ripening and ripe fruit is infested, clean pick all ripe and overripe fruit and discard it to remove the developing SWD population from the planting. After clean picking and sanitation, apply an effective insecticide to protect the ripening fruit.
Discard infested fruit in clear plastic bags held in the sun to solarize and kill larvae or freeze it. Holding culled fruit in tightly closed plastic bags will prevent SWD adults to emerge from the infested fruit into the environment.
High temperature will dissuade SWD, but hot days this past week in NY have been followed by cool nights which has likely allowed SWD adults to escape the impact of the heat. High humidity is conducive to SWD development, so that factor will also weigh in to make management difficult this fall. The microclimate in the fruit planting can be altered with pruning practices, so plan now to prune for a more open plant canopy in 2016.
Consult the resources in the right hand side bar for more information on SWD.
Berry Growers, Industry and Extension Friends…plan to attend the SWD Management Open House! Wednesday, September 2nd from 3:00-5:00 PM at The Berry Patch of Stonewall Hill Farm, 15589 NY Route 22, Stephentown, NY 12168 in Rensselaer County.
At the Field Meeting you will learn and see…
- How to do an easy salt floatation test to detect SWD in fruit.
- Research results on commercial lures for monitoring SWD adults with traps.
- Tour a blueberry planting surrounded by SWD exclusion netting.
- A fixed sprayer system in a high tunnel raspberry planting.
- The effectiveness of clean picking, sanitation and refrigeration against SWD.
Farm owner and President of the NYS Berry Growers Association (NYSBGA), Dale Ila Riggs, will host the SWD Open House to showcase the SWD research that has been funded by allocations from the New York State legislature to the NYSBGA.
The Eastern NY Commercial Horticulture Program of Cornell Cooperative Extension has coordinated the SWD Open House. The featured research and development on SWD lures and the fixed sprayer system has been led by faculty in the College of Agriculture and Life Sciences at Cornell University.
Sign up to attend! Call Marcie at 518-272-4210—a headcount is needed to make handouts. If you get voicemail, leave your name, phone number, and the number who will attend the SWD Open House at The Berry Patch.
This event will happen rain or shine on Wednesday, September 2nd from 3:00-5:00 PM at The Berry Patch, 15589 NY Route 22, Stephentown, NY.
Questions? Contact Laura McDermott: 518-791-5038
Research supported by funding from:
Northeast Sustainable Agriculture Research and Education (NE SARE)
New York Farm Viability Institute (NYFVI)
New York State Legislature
Two SWD were caught on August 18, 2015 in traps set in raspberry & blueberry in Steuben County. This site is being monitored by Stephanie Mehlenbacher, Steuben County Cornell Cooperative Extension. (GDD = 1776, day length = 13:44)
Only three sites in the NY monitoring network have not yet reported SWD finds. If you have ripe or ripening fruit to be harvested, consider a strict regimen to manage SWD: judicious insecticide applications (tree fruit, grapes, berry crops), immediate refrigeration of harvested fruit, squashing any fruit that falls to the ground, clean picking overripe and unmarketable fruit, weed control, and pruning to maintain an open canopy and promote earlier bearing in brambles.
Three SWD, two female and one male, were caught on August 11, 2015 in traps set in blueberry. The SWD were in the trap set on the edge of the crop. This site is being monitored by Jim O’Connell, Ulster County Cooperative Extension and Eastern NY Commercial Horticulture Program. (GDD = 2019, day length = 14:00)
It is very likely that SWD is present across NY State wherever tender, ripe fruit is found. Consider what your SWD management strategy will be. Make plans for dealing with this introduced, invasive pest in your berry crops by reading up on horticultural strategies that make sense in the era of SWD.
Now found in 25 of 28 (89%) of Counties in the SWD monitoring network, 2015 will be challenging for late fruit crops in NY. Traps have caught SWD two weeks in a row in 22 of the 25 NY Counties reporting SWD finds.
Of the 48 monitoring sites across NY, only 5 have not yet caught SWD; 90% of all SWD monitoring sites have positive reports of SWD caught in traps.
Some monitoring network participants are sampling fruit, when SWD is first caught in traps, and checking for infestation with salt floatation. At first trap catch, most fruit samples have few to no SWD larvae or eggs in a 50-fruit sample. Monitor your fruit for symptoms and signs of SWD infestation using the methods described in the blog, Do my fruit have SWD?
Those sites where SWD hasn’t been caught yet are characterized as having fruit that is not yet ripe, such as fall raspberry, or low fruit set possibly due to the cold winter, such as in blueberry.
Some monitoring sites reported high numbers of SWD in late July/early August, the second consecutive week of trap catch – e.g. 83 in Washington County, 40 in Cayuga County. Cooperators are pulling traps once at sustained catch.
Researchers in Greg Loeb’s lab, Department of Entomology, Geneva, studying different lures in the Finger Lakes region are now catching 20-40 SWD per trap. Sites in their study with rigorous spray schedules catch less than 10 SWD per trap. Research projects are wrapping up, too.
Our focus is to provide early warning of SWD arrival in NY State. We will continue reporting on the SWD monitoring network until all sites have caught SWD. If you have any questions, suggestions or comments, please let me know.
14 SWD were caught today, August 17, 2015, in traps set in blueberry in Clinton County, 10 males in traps set in the interior of the crop and 4 males in traps set on the edge of the crop. These traps are being monitored by Lindsey Pashow, technician, and Amy Ivy, educator & director, Clinton County Cornell Cooperative Extension. These males may be lonely…? Another review of trap contents on Wednesday will confirm whether females are absent. Regardless, don’t think for a minute that absence of females means your crop is safe. They could be out laying eggs and ignoring the lure of food provided by the traps. Only three Counties in the 29-County network have not yet caught SWD (Columbia, Dutchess, and Steuben). If your crop is ripe – take steps to manage SWD. If your crop is on the verge of ripening – make plans to protect it from SWD. (GDD = 1793, day length = 13:55)
An important warning from Dow AgroSciences, the manufacturer and distributor of the organic-approved insecticide, Entrust SC, about the use patterns of this product for control of SWD – don’t overuse it, follow label directions and rotate with a different active ingredient. (Excerpts from their letter are in quotes. I’ve added bold emphasis.)
It is crucially important to follow the “labeled resistance management restrictions for Entrust SC in organic cropping systems in the Northeastern United States targeting Spotted Wing Drosophila.” It is my understanding that, in New York, Entrust is under a 2ee registration and you must have the 2ee in your possession when applying this insecticide; ask your supplier.
“Entrust SC Insecticide is a solution for control of economically important arthropods across many different crops. This product is registered for organic use and is OMRI certified. The active ingredient Spinosad is a group 5 insecticide, which offers a unique mode of action. Dow AgroSciences is proud to offer a unique class of chemistry for organic growers.”
Insecticide rotation to different IRAC groups
“At Dow AgroSciences we take (insecticide) resistance very seriously and investigate all situations we are aware of in which non-compliance may be occurring or where performance is in question. We strive to make sure our products are stewarded correctly in the market to follow label language with regards to use patterns. Specifically, our labels include Resistance Management directions which state that rotation to other insecticide classes should occur after two consecutive applications.” For many fruit crops, only three total applications of Entrust may be applied per season—read and follow label directions.
Organic insecticide rotation guidelines -
For organic management of SWD, rotate to a different insecticide active ingredient after applying one, no more than two or three (depending on the crop label) Entrust (group 5 insecticide) sprays. Options for rotation partners include the active ingredients azadirachtin (group UN insecticide) and pyganic (group 3A insecticide). While spinosad (Entrust) has good to excellent activity against SWD, azadirachtin and pyrethrin have fair to poor activity against SWD. Save Entrust applications for when SWD populations are high and fruit is at high risk.
Azadirachtin is the active ingredient derived from neem oil. Trade names include, but are not limited to, AzaSol, Aza-Direct, AzaGuard, AzaMax, and Azatrol EC. These insecticides may not be labeled on all fruit crops, so read the label carefully before purchasing and using this insecticide. Group UN – mode of action is unknown or uncertain.
Pyrethrins are active ingredients derived from the plant Chrysanthemum cinerariifolium. Pyrethrin insecticides are highly toxic to bees, so don’t use these when pollinators are active. Trade names include, PyGanic EC 1.4 and PyGanic EC 5.0. These insecticides may not be labeled on all fruit crops, so read the label carefully before purchasing and using this insecticide.
Insecticide application frequency and amounts per season
Dow AgroSciences has also “been made aware that Entrust SC is allegedly being used at a greater frequency than the label allows per crop. Dow AgroSciences is closely monitoring this situation to understand if these are isolated cases or more widespread occurrences.” Entrust is typically limited to 3-5 applications per season, depending on the fruit crop, and always no more than a cumulative total of 9 oz per acre per season.
When an insecticide is applied too often and at higher cumulative rates than research on the chemistry warrants, a sensitivity shift in the target insects can occur over the course of a growing season. Over several growing seasons, SWD individuals with reduced Entrust SC (Spinosad) sensitivity could make up the majority of the SWD population in organic cropping systems. We are very concerned about this and work is ongoing to identify more effective insecticides for rotation partners in organic systems.
If resistance to Entrust SC (Spinosad) is selected in organic systems due to overuse and lack of rotation, IPM growers using the group 5 insecticide Delegate WG (Spinetoram) could lose this insecticide due to group 5 insecticide sensitivity shifts in the SWD population. Spinetoram is the chemically synthesized spinosad active ingredient and it, currently, has excellent activity against SWD—it, too, should not be overused. Likewise, if IPM growers overuse Delegate, this could have negative repercussions on the activity of Entrust.
Let’s keep Entrust in the Northeast!
“…if non-compliance continues then Dow AgroSciences will pursue corrective action which could include withdrawal of Entrust SC from the Northeastern United States. If you have any questions, please contact your local Dow AgroSciences partner.”
Take the time to learn about resistance management and follow the label directions that are designed to help prevent this from occurring.
One female SWD was caught on August 5, 2015 in a trap set in a blueberry planting in Herkimer County. Traps at this location are being monitored by Bernie Armata, Herkimer County Cornell Cooperative Extension Association. (GDD = 1601, day length = 14:18)
To date, only four counties (Clinton, Columbia, Dutchess, and Steuben) have not caught SWD. In these sites, fruit is either unripe or the crop is blueberry, which can be tricky for trap catch with our current traps.
Two SWD at one location & one SWD at a second location in Tioga County were caught the week of August 3, 2015. At both locations the traps were in raspberry and are being monitored by Michele Kline, Regional Fruit & Vegetable Specialist, Tioga County Cornell Cooperative Extension. (GDD = 1562 & 1740, day length = 14:10 & 14:09, respectively.)
One male SWD was caught on August 4, 2015 in a trap set in fall raspberry in southern Essex County. The report comes in from Amy Ivy, Clinton County Cornell Cooperative Extension and Eastern NY Horticulture Program. The raspberries at this site are just starting to ripen. (GDD = 1602, day length = 14:24)
In response to Amy’s finding, Laura McDermott replied, “The pressure we are experiencing (in the Capital District) right now makes me want growers to be as pro-active as possible. The fact that you found (SWD) in a crop that hasn’t even started harvest yet is significant – and I would advise people to get ready to start spraying. I’ve been getting calls from around the state from folks that are seeing (SWD) that haven’t really been bothered much since 2012.”
2015 is going to be a challenging year for SWD management. It is time to take SWD management seriously.keep looking »