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The Sustainable SWD Management Project's November 5 webinar will cover the seasonal biology and movement of SWD. So... Mark your calendars!

This webinar is next week! "SWD in Space and Time: What do we know about the seasonal biology and movement of SWD?" is scheduled for November 5, 2019 at 1:00 pm EST.

Picture showing SWD on a raspberry.
Meet and greet - male (right) and female (left) SWD - on a raspberry fruit.

You'll gain information on:

  • how SWD populations develop over time,
  • how they move during the day,
  • how they move throughout the year,
  • how they survive during the winter.

You'll learn how to apply this new knowledge to improve your SWD management practices.

The Sustainable SWD Management Project (swdmanagement.org) looks forward to sharing this information with you!

Receive reminders about this webinar by completing this form here: forms.gle/ubqnNorrJVcsxCF89

View the webinar on Tuesday, November 5, starting at 1:00 pm EST here:
go.ncsu.edu/swd-webinar

Sign on a few minutes early to complete a short registration form before the webinar starts.

Any questions? Please contact Hannah Burrack, North Carolina State University, (hjburrac@ncsu.edu) with questions. You've enjoyed Hannah's SWD photos on this blog!

Fruit that has dropped to the ground in orchards and berry plantings provides resources for SWD — food and reproduction. Populations of SWD are climbing. SWD made up almost half of the fruit flies caught in traps in an unsprayed research site where ~300 were caught in four traps.  I've seen lots of fruit flies (of various species, including the distinctive male SWD) flitting around the dropped apples in my yard that have been chewed on and pecked at by chipmunks, squirrels, and my chickens (this particular apple tree has been defoliated by apple scab this year and won't carry the crop.)

Picture showing an SWD larva in a pokeweed berry.
SWD larva in a pokeweed berry. Pokeweed is a very suitable host for SWD reproduction.

WEEDS! Pokeweed fruit are starting to ripen; SWD thrives in those fruit.

We've got a long way to go before the SWD season is over. This is the time of year that management has to be consistent and constant:

  • maintain an appropriate insecticide program
  • routinely sample fruit with salt flotation to check for larvae
  • keep weeds down
  • prevent leaks in irrigation systems (gosh, it's like a water paradise for SWD!)
  • keep plants well pruned and staked
  • remove cull fruit from the planting or drop it to the ground

And, while I'm on the subject of cull fruit, I've revised the SWD insecticide guide for treating dropped fruit on the ground. Here's the link to the Quick Guide to SWD insecticides for treating dropped fruit, www.hort.cornell.edu/fruit/pdfs/swd/drop-cull-insecticides.pdf . Make sure to refresh your browser so you don't pull up last year's — the new one should say August 2019 on it.

Keep on top of SWD Management, review the SWD Management pages on Cornell Fruit Resources, fruit.cornell.edu/spottedwing/management/.

Spotted Lanternfly — On the Doorstep Or Already In Our Fields? Learn more at the 2019 IPM Conference hosted by the New York State Integrated Pest Management Program on August 15, 2019 at the Broome County CCE Farmers Market, 840 Upper Front St., Binghamton, NY. Yes! That's this Thursday, 8:30 to 4:30. Lunch provided. Earn recertification credits.

Register at: lergp.cce.cornell.edu/event.php?id=416

It’s not if but when and where this invasive pest will show up in New York State (NYS). Be on the front line of stopping the invasion!

Learn where to look for it; how to correctly identify it; how to best report sightings of it.

Watercolor of spotted lanternfly adults by Karen EnglishSpotted Lanternfly is a concern to: Growers; Foresters; Nursery, Greenhouse and Christmas Tree Operations; Landscapers; Master Gardeners — all NYS residents. In fact, anyone whose business or travel takes them through quarantine zones should understand New York State’s regulations.

Experts from across PA and NY will provide updates on what is being done to prevent Spotted Lanternfly's (SLF’s) establishment in New York. Learn about the tools available to combat this threat to our fields, forests, and homes. Here's a sampling of what you'll hear about:

  • News from the Front Line.  Current research on SLF biology, movement and management.  Keynote Speaker – Julie Urban, Penn State University
  • The NYS External Quarantine and You.  Who needs to comply and how does it work? - Thomas Allgaier, NYS Dept of Agriculture & Markets
  • I Can’t Go Outside! Impact of SLF on green industry and residential areas. -Emelie Swackhamer, Penn State Extension
  • Working with Your Local PRISM to Prevent the SLF Invasion. - Patty Wakefield Brown, Finger Lakes Partnership for Regional Invasive Species Management (PRISM)
  • The Million Dollar Impact: Management strategies for the grape industry and other perennial fruit crops. - Tim Weigle, NYS IPM Program
Picture of an adult spotted lanternfly on a tree trunk
Spotted lanternfly adult on the trunk of a tree.

Register at: lergp.cce.cornell.edu/event.php?id=416

Find out more about this insect that threatens to invade New York State on the NYS IPM Program SLF IPM Conference Website, nysipm.cornell.edu/resources/nys-ipm-conferences/spotted-lanternfly-our-doorstep/

Lunch is included with your registration. Pick up materials, cards, brochures, fact sheets — on SLF and more — during breaks. Visit with professionals working on the frontline, ask questions, get answers. Register at: lergp.cce.cornell.edu/event.php?id=416

Picture of the fourth-instar nymph of spotted lanternfly.
Fourth instar of spotted lanternfly, before the adult stage.

Recertification credits. The Spotted Lanternfly IPM Conference has been approved for 7.5 Certified Nursery Landscape Professional credits, and 6 NYS Pesticide Recertification credits in the categories of 1a, 2, 3a, 6a, 9, 10, 22 and 25.

This Statewide Public Conference is sponsored by The NYS Dept of Agriculture and Markets, NYS Dept of Environmental Conservation, Hobart and William Smith Colleges, the Finger Lakes Institute, the Finger Lakes PRISM, Cornell University and the NYS IPM Program.

WHAT: IPM Conference, Spotted Lanternfly — On the Doorstep Or Already In Our Fields?

WHEN: Thursday, August 15, 2019 from 8:30 AM to 4:30 PM 

WHERE: Broome County CCE Farmers Market, 840 Upper Front St., Binghamton, NY

If you thought SWD was bad... This invasive is even worse! Feeding en mass, SLF suck the very life juices from plants and shower everything below with their excreted honeydew, favoring a lawn of sooty molds. Ugh. September is the month for dispersing adults — let's get ready!

Register now at: lergp.cce.cornell.edu/event.php?id=416

Blueberries are highly susceptible to SWD. Although early maturing varieties can escape infestation in some years, that hasn’t been the case this year in many areas of NY State. U-Pick and farm stand customers want the best from farm-fresh blueberries and SWD can mar that experience — so be proactive — make sure your customers know what you’re up against. Wholesale and processing blueberry growers know there’s zero tolerance for SWD in fruit at the retailer and processor. It’s time to learn how to protect this crop to protect your markets!

A picture showing two male SWD on a blueberry.
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 female SWD fruit flies can lay eggs in ripe blueberries, but also in ones that are ripening, even only pink. And because SWD has been caught at all monitoring locations across NY State, it is fair to say that the blueberry harvests currently underway are highly vulnerable to infestation.

An insecticide program is an essential component of managing SWD in blueberries; this year it will be in early-, mid-, and late-season varieties.

Things to consider regarding insecticide programs for SWD, with specific emphasis on materials registered for blueberries:

  • Population growth models for SWD calculate, theoretically, that using the most efficacious insecticide first will more successfully lower SWD numbers by knocking the population back to close to zero and delaying population growth. (This is strikingly similar to classic principles of plant disease epidemiology and tactics in plant disease management.)
  • Rotate use among insecticides with different IRAC groups -- related to the mode of action of the insecticide -- to reduce selection pressure for insecticide-resistant populations of SWD. (IRAC codes are usually given on the first page of the pesticide label near the product name. For example, Group 3A Insecticide.
  • Insecticides with probable excellent efficacy include – Delegate WG (3 days), Delegate WG supplemental label (1 day), Exirel (3 days), Bifenture 10DF (1 day), Brigade WSB 2(ee) (1 day), Danitol 2.4EC (3 days), and Mustang Maxx (1 day), Lannate SP (3 days), Lannate VP (3 days), and Imidan (3 days). Of these, choose first the one with the longest pre-harvest interval (given in parentheses) that you can accommodate; some may be out of the question at this point. Rotate to other insecticides with shorter pre-harvest intervals for closer to harvest.
  • After using a highly efficacious insecticide, for the subsequent application, it is usually adequate to use an insecticide that has lower efficacy – Entrust Naturalyte 2(ee) (3 day3), Entrust SC 2(ee) (1 day), Assail 30SG 2(ee) (1 day), Malathion 5EC 2(ee) (1 day), Malathion 8 Aquamul 2(ee) (1 day), or Malathion 57 2(ee) (1 day).
  • For organic production, Entrust Naturalyte 2(ee) (3 days) and Entrust SC 2(ee) (1 day) are the most efficacious organically-approved insecticides. Rotate this active ingredient with either Pyganic (0 days), AzaSol (0 days), Grandevo (0 days), or Venerate (0 days) along with shortening the number of days between the spray intervals.
  • The spray interval column in the Insecticide Quick Reference Guide table relates to use of the same product back-to-back. When switching to another mode of action, more frequent applications are OK and are suggested against SWD.
  • Rainfast? Research on berries has shown Mustang Maxx isn’t very rain fast, so plan to re-cover if significant rain occurs during the spray interval. This is good practice with SWD or any insecticide program if the rainfall meets or exceeds an inch of rain.
  • Don’t stretch intervals between sprays more than seven days.
  • Get excellent coverage. Spray every row (no alternate row spraying.)

Review the Quick Reference Guide to SWD Insecticides for berries at
www.hort.cornell.edu/fruit/pdfs/swd/berry-insecticides.pdf

Other tactics that can help considerably are:

Re-set blueberry fields: Because blueberries don’t all ripen at the same rate in the fruit cluster, it is possible and advisable to “re-set” the field. When fruit infestation is found via salt flotation or high numbers of SWD are caught in traps in the field, clean pick all ripe and cull fruit. Remove cull fruit from the planting and solarize it or freeze it to kill SWD. Solarize in sealed, clear plastic bags set in the sun. After clean picking, spray insecticide. Choose a material with excellent efficacy against SWD and an appropriate days-to-harvest interval.

Sanitation: Pick off and remove all cull fruit from the planting. Routine sanitation can be very beneficial in IPM – it eliminates SWD food and egg-laying resources and slows population growth. And when done routinely, it takes a lot less time and is a lot more effective. Cull fruit can be placed in clear plastic bags and left in the sun to bake or placed in a freezer to kill SWD eggs and larvae.

Mowing: Keeps the environment in the plant’s microclimate hot, sunny, and dry. On diversified farms, do be careful when timing mowing or renovation of strawberry fields so as to reduce movement of SWD from that crop into the next ripening crop on your farm. See last year’s blog on strawberry renovation, blogs.cornell.edu/swd1/2018/06/27/renovate-strawberry-plantings-promptly/.

Weed management: Keeps the environment in the plant’s microclimate hot, sunny and dry, and provides no alternate hosts. Be mindful of crops no longer being harvested. Cull fruit, unprotected with insecticide, left in those fields will provide resources for SWD population growth.

Pruning: Keeps the environment in the plant’s microclimate hot, sunny and dry, and improves spray penetration and deposition. Prune blueberries yearly. Prune shoots at the base of the plant, don’t prune out portions of shoots. Leave the best two shoots in each age category when pruning established plantings. This keep the plant balanced, growing vigorously, and fruiting well.

Cold storage: Put harvested fruit into a cooler at 32-34 F as soon as possible after harvest. Hold it there to slow and kill SWD larvae and eggs. Blueberries can tolerate 32 F storage conditions.

Consult Cornell Fruit Resources SWD Management, fruit.cornell.edu/spottedwing/management/.

Monitoring tips for SWD

Salt flotation: Routinely sample a subset of fruit that’s being harvested using salt flotation to alert you to the presence of larvae in fruit. A simple method for this is in Guidelines for Checking Fruit for SWD Larvae in the Field by Laura McDermott, Download it from the Cornell Fruit Resources SWD Monitoring page, fruit.cornell.edu/spottedwing/monitoring/.

Two growers describe their success using salt flotation to monitor infestations in blueberries, detailed on the blog, Use salt flotation to check for SWD, blogs.cornell.edu/swd1/2018/09/11/use-salt-flotation-to-check-for-swd/

Picture of three SWD males.
Three male spotted wing Drosophila. Note the spot on each wing, which is on the end of the first vein from the outer edge of the wing.

Traps: It is relatively easy to use red or yellow sticky cards to monitor for the distinctive male SWD in fruit plantings. Set the sticky card traps on the edge of the planting where it is convenient to read them daily. Use a coffee stirrer to scrape off and discard the stuck insects daily and replace the sticky card when its stickiness has worn off. Here’s one place you can order trap and lure supplies – Great Lakes IPM, www.greatlakesipm.com/.

SWD populations will build rapidly when fruit is available for oviposition sites, during warm, humid, cloudy weather, and wherever crop canopies are dense and weeds are not managed or mowed. A mated female can lay about 1-3 (or more) eggs per fruit, 7-16 eggs per day, and about 350 eggs during her life span of about three weeks.

So stay informed!

Comprehensive information on SWD IPM is available in Spotted Wing Drosophila IPM in Blueberries from the NE IPM Center SWD Working Group, neipmc.org/go/swdpub2

Consult Cornell Fruit Resources SWD Management, fruit.cornell.edu/spottedwing/management/.

Refer to the Cornell Pest Management Guidelines, cropandpestguides.cce.cornell.edu/ and always have the latest version -- the 2019 version for Berry Crops.

For organic growers, Management Recommendations for Spotted Wing Drosophila in Organic Berry Crops, www.canr.msu.edu/ipm/uploads/files/SWD/SWDOrganicBerryCrops.PDF

SWD prefers nice ripe fruit — like we do! And blueberries are sooo delicious!

Sustained SWD catch was obtained over the last couple of weeks in several counties — Dutchess 1 SWD, Herkimer 6 SWD, Livingston 18 SWD, Onondaga 16 SWD, Orleans at two farms 11 and 9 SWD, and Tioga 1 SWD. Last month, I missed reporting sustained catch in Erie County on June 6, 1 female SWD. Blueberries, raspberries, cherries, gooseberries, currants and many other fruits are being harvested and many will continue with harvests extending over the next several weeks.

Risk from SWD infestation will be high from this point forward in the growing season. Monitor your crops for infestation by taking a sample of fruit at each harvest period and doing a salt flotation test on it. Methods described in Guidelines for Checking Fruit for SWD Larvae in the Field by Laura McDermott, available on Cornell Fruit Resources Monitoring SWD page, fruit.cornell.edu/spottedwing/monitoring/.

Symptoms of SWD infestation in raspberry. The fruit receptacle is stained red with leaking juice, druplets are damaged and dimpled, and fruit melts off the receptacle.
Signs of SWD infestation on raspberry. The fruit receptacle is stained red with leaking juice, druplets are damaged and dimpled, and fruit melts off the receptacle.

Look for signs of infestation in fruit in the field -- look for symptoms of leaky fruit; tiny drops of juice on otherwise perfect fruit; red stains on raspberry fruit receptacles that would otherwise be white; flat, sunken, and dull spots or dimples on fruit surfaces; distorted and disintegrating fruit; leaves stained with juice that has leaked from infested fruit.

Protect ripe and ripening fruit crops from infestation with an insecticide program. Choose a material with excellent efficacy against SWD and an appropriate days-to-harvest interval. Download the Quick Reference Guide to SWD Insecticides at

www.hort.cornell.edu/fruit/pdfs/swd/berry-insecticides.pdf for berries

www.hort.cornell.edu/fruit/pdfs/swd/treefruit-grape-insecticides.pdf for stone fruit and grapes

Details about each County's sustained catch:

  • Dutchess: 7/16/2019, 1 female, raspberry – total 1
  • Erie: 6/6/2019, 1 female, blueberry – total 1
  • Herkimer: 7/15/2019, 2 females & 4 males, blueberry – total 6
  • Livingston: 7/25/2019, 7 females & 11 males, tart cherry – total 18
  • Onondaga: 7/16/2019, 7 females & 9 males, blueberry – total 16
  • Orleans: 7/29/2019, 10 females & 1 male, raspberry – total 11
  • Orleans: 7/29/2019, 7 females & 2 male, raspberry – total 9
  • Tioga: 7/17/2019, 1 female & 0 males, blueberry – total 1

The sustained catch in Tioga County of only 1 SWD in the blueberries after the prior week’s catch of 26 underlines the impact of an insecticide program on SWD populations.

Thank you for monitoring SWD in the Counties with sustained catch!

  • Peter Jentsch and Lydia Brown, Hudson Valley Research Laboratory (Dutchess County)
  • Sharon Bachman, CCE of Erie County (Erie County)
  • David Thorp, CCE of Livingston County (Livingston County)
  • Shona Ort and Barb Neal, CCE of Chemung County and CCE of Tioga County (Tioga County)
  • Elizabeth Tee, Lake Ontario Fruit Program (Orleans County)
  • Ryan Parker and Juliet Carroll, CCE NYS IPM Program (Herkimer and Onondaga County)

This wraps up monitoring for this year.

The ability for the SWD population to explode as summer rolls on was demonstrated last week in several counties where I have research projects. Per trap, 5 to 125 SWD were caught in raspberry, blueberry, and tart cherry in mid-July. The totals for the two to four traps set in the orchards and fields were 14 to 250.

Use this summary as a wake up call! For the weeks ending on the date given:
7/11/2019, Schuyler County, blueberry, 4 traps, 22 SWD (11 males and 11 females)
7/11/2019, Schuyler County, raspberry, 4 traps, 108 SWD (64 males and 44 females)
7/22/2019, Herkimer County, blueberry, 4 traps, 30 SWD (12 males and 18 females)
7/22/2019, Wayne County, tart cherry, 2 traps, 14 SWD (1 male and 13 females)
7/22/2019, Wayne County, tart cherry, 2 traps, 24 SWD (4 males and 20 females)
7/22/2019, Wayne County, tart cherry, 2 traps, 57 SWD (9 males and 48 females)
7/22/2019, Wayne County, tart cherry, 2 traps, 85 SWD (19 males and 66 females)
7/22/2019, Wayne County, tart cherry, 2 traps, 250 SWD (60 males and 190 females)
7/23/2019, Wayne County, blueberry, 2 traps, 131 SWD (53 male and 78 females)
7/23/2019, Wayne County, blueberry, 4 traps, 29 SWD (14 male and 15 females)

In eight of the nine sites a spray program was in place to protect fruit. Fruit is ripe and being harvested – and it’s delicious! Fruit isn’t showing signs of infestation, which means insecticide programs can protect fruit from oviposition, even when SWD numbers are high. Download the Quick Reference Guide to SWD Insecticides at

Photo of the three instars of SWD.
The three instars of SWD will emerge from fruit immersed in a salt solution. The smallest instar is about 0.5 mm long, the largest about 2 mm long.

Salt flotation – What  these numbers also demonstrate is that trap catch numbers aren’t necessarily an indication of whether or not an insecticide program is working. A better indication is to sample fruit and run a salt flotation test. Two berry growers described their success last year using salt flotation to monitor infestations in blueberries, detailed on the blog, Use salt flotation to check for SWD.  A simple method is described in Guidelines for Checking Fruit for SWD Larvae in the Field by Laura McDermott, which can be downloaded from Cornell Fruit Resources SWD Monitoring pages, fruit.cornell.edu/spottedwing/monitoring/. Large scale berry growers will routinely run salt flotation at each harvest, because blueberries, raspberries, and blackberries ripen and are harvested over several weeks. For crops that are harvested all at once, like tart cherry, salt flotation may not be as useful.

Refrigeration – The high populations of SWD, coupled with later ripening of many crops this year, make it even more important to immediately cool fruit after harvest. Cold storage temperatures close to 32°F can greatly inhibit and even kill SWD in fruit. Raspberries, blackberries, blueberries, and tart cherries will all tolerate cold storage temperatures between 32°F to 34°F.

Diversified fruit farms – Protect your crops from SWD, if you’re growing susceptible fruit – June strawberries, day-neutral strawberries, sweet cherries, tart cherries, raspberries, blackberries, elderberries, blueberries, peaches, nectarines, plums, prunes, and thin-skinned grapes. If you have a diversified fruit farm, SWD can spill over from one crop to the next as they are harvested and especially when cull fruit remains in the field. Renovate strawberry fields promptly.

Photograph of high tunnel raspberries.
High tunnel raspberries.

Fruit becomes susceptible to SWD oviposition when it is ripening and is highly susceptible when it is ripe – raspberry, blackberry, blueberry, sweet cherry, tart cherry, elderberry. Fruit that is less susceptible will be attacked when it is at peak ripeness – peach, nectarine, plum, prune, strawberry, grapes. All fruit can serve as a resource for feeding and breeding when it is left for cull in the field. The good news is that, in degraded fruit, SWD doesn't compete all that well with other Drosophilas, like Drosophila melanogaster, our common vinegar fly, which often shows up in our kitchens in late summer or in the winery during press. SWD prefers nice ripe fruit — like we do!

Raspberries are just about the most susceptible fruit crop grown in New York State. It’s time to learn how to protect this crop! Fruit that is ripening and ripe is at risk of infestation. SWD has been caught at all but one of the monitoring locations across the State and raspberry harvests are underway.

Picture showing SWD on a raspberry.
Meet and greet - male (right) and female (left) SWD - on a raspberry fruit.

This year summer raspberry (floricane types) won’t escape infestation simply because their fruiting season is earlier than fall raspberry (primocane types). Both types of raspberries will be highly vulnerable.

An insecticide program is an essential component of managing SWD in fall raspberries; this year it will be in summer raspberries, as well. Things to consider regarding insecticide programs for SWD, with specific emphasis on materials registered for raspberries:

  • Population growth models for SWD calculate, theoretically, that using the most efficacious insecticide first will more successfully lower SWD numbers by knocking the population back to close to zero and delaying population growth. (This is strikingly similar to classic principles of plant disease epidemiology and tactics in plant disease management.)
  • Rotate use among insecticides with different IRAC groups — related to the mode of action of the insecticide — to reduce selection pressure for insecticide-resistant populations of SWD.
  • Insecticides with probable excellent efficacy include – Delegate WG (1 day), Bifenture 10DF (3 days), Brigade WSB 2(ee) (3 days), Brigade EC 2(ee) (3 days), Danitol 2.4EC (3 days), and Mustang Maxx (1 day). Of these, choose first the one with the longest pre-harvest interval (given in parentheses) that you can accommodate; some may be out of the question at this point. Rotate to other insecticides with shorter pre-harvest intervals for closer to harvest.
  • After using a highly efficacious insecticide, for the subsequent application, it is usually adequate to use an insecticide that has lower efficacy – Entrust Naturalyte 2(ee) (1 day), Entrust SC 2(ee) (1 day), Assail 30SG 2(ee) (1 day), Malathion 5EC 2(ee) (1 day), Malathion 8 Aquamul 2(ee) (1 day), Malathion 57 2(ee) (1 day), or Molt-X (0 days).
  • For organic production, Entrust 2(ee) (1 day) (Naturalyte and SC formulations) is the most efficacious organically-approved insecticide. Rotate this material with either Pyganic (0 days), AzaSol (0 days), Grandevo (0 days), or Venerate (0 days).
  • The spray interval column in the Insecticide Quick Reference Guide table relates to use of the same product back-to-back. When switching to another mode of action, weekly applications are OK and are suggested against SWD.
  • Research on berries has shown Mustang Maxx isn’t very rain fast, so plan to re-cover if significant rain occurs during the spray interval.
  • Don’t stretch intervals between sprays more than about seven days.
  • Get excellent coverage. Spray every row (no alternate row spraying.)

Review the Quick Reference Guide to SWD Insecticides for berries at www.hort.cornell.edu/fruit/pdfs/swd/berry-insecticides.pdf

Other tactics that can help considerably are:

Picture of a male SWD on a blackberry.
Male SWD on blackberry in August.

Re-set raspberry and blackberry fields: Because raspberry and blackberry continue to flower and set fruit over a protracted period of time, it is possible and advisable to “re-set” the field. When fruit infestation is found via salt flotation or high numbers of SWD are caught in traps in the field, clean pick all ripe and cull fruit. Remove this fruit from the planting and solarize it or freeze it to kill SWD. Solarize in sealed, clear plastic bags set in the sun. After clean picking, spray insecticide. Choose a material with excellent efficacy against SWD and an appropriate days-to-harvest interval.

Sanitation: Pick off and remove all cull fruit from the planting. Routine sanitation can be very beneficial in IPM — it eliminates SWD food and egg-laying resources and slows population growth. And when done routinely, it takes a lot less time and is a lot more effective. Cull fruit can be placed in clear plastic bags and left in the sun to bake or placed in a freezer to kill SWD larvae.

Mowing: Keeps the environment in the plant’s microclimate hot, sunny, and dry. On diversified farms, do be careful when timing mowing or renovation of strawberry fields so as to reduce movement of SWD from that crop into the next ripening crop on your farm. See last year’s blog, Renovate strawberry plantings promptly, blogs.cornell.edu/swd1/2018/06/27/renovate-strawberry-plantings-promptly/.

Weed management: Keeps the environment in the plant’s microclimate hot, sunny and dry, and provides no alternate hosts.

Pruning: Keeps the environment in the plant’s microclimate hot, sunny and dry, and improves spray penetration and deposition. Find out details about how this can be done in raspberry on this blog, Pruning caneberries to minimize SWD habitat within the planting, blogs.cornell.edu/swd1/2017/06/27/pruning-caneberries-to-minimize-swd-habitat-within-the-planting/

Cold storage: Put harvested fruit into a cooler at 32-34 F as soon as possible after harvest. Hold it there to slow and kill SWD larvae and eggs. Raspberries can tolerate 32 F storage conditions.

Consult Cornell Fruit Resources SWD Management, fruit.cornell.edu/spottedwing/management/.

Monitoring tips for SWD

Salt flotation: Routinely sample a subset of fruit that’s being harvested using salt flotation to alert you to the presence of larvae in fruit. A simple method for this is in Guidelines for Checking Fruit for SWD Larvae in the Field by Laura McDermott, available on Cornell Fruit Resources SWD pages at cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/0/7265/files/2017/01/SaltFloatation-2kmt284.pdf.

A grower checks a blueberry fruit sample for SWD larvae using salt flotation.
Checking fruit for larva with salt flotation at the Albany workshop.

Two growers describe their success using salt flotation to monitor infestations in blueberries, detailed on the blog, Use salt flotation to check for SWD, blogs.cornell.edu/swd1/2018/09/11/use-salt-flotation-to-check-for-swd/

Traps: It is relatively easy to use red or yellow sticky cards to monitor for distinctive male SWD's in fruit plantings. Set the sticky card traps on the edge of the planting where it is convenient to read them daily. Use a coffee stirrer to scrape off and discard the stuck insects daily and replace the sticky card when its stickiness has worn off. Here’s one place you can order trap and lure supplies – Great Lakes IPM, www.greatlakesipm.com/.

SWD populations will build rapidly when fruit is available for oviposition sites, during warm, humid, cloudy weather, and wherever crop canopies are dense and weeds are not managed or mowed. A mated female can lay about 1-3 (or more) eggs per fruit, 7-16 eggs per day, and about 350 eggs during her life span of about three weeks.

So stay informed!

Comprehensive information on SWD IPM is available in Spotted Wing Drosophila IPM in Raspberries & Blackberries from the NE IPM Center SWD Working Group, neipmc.org/go/swdpub1

Consult Cornell Fruit Resources SWD Management, fruit.cornell.edu/spottedwing/management/.

Refer to the Cornell Pest Management Guidelines, cropandpestguides.cce.cornell.edu/ and always have the latest version -- the 2019 version for Berry Crops.

For organic growers, Management Recommendations for Spotted Wing Drosophila in Organic Berry Crops, www.canr.msu.edu/ipm/uploads/files/SWD/SWDOrganicBerryCrops.PDF

SWD prefers nice ripe fruit — like we do! Let’s keep our fruit to ourselves!

Sustained SWD catch in Eastern NY — Columbia County 5 SWD, Clinton County 5 SWD, & Orange County 36 SWD — and Wayne County 4 SWD. Berries and cherries are being harvested and will continue ripening over the next several weeks. Risk from SWD infestation will be high from this point forward in the growing season.

Monitor your crops for infestation by sampling fruit at each harvest period and doing a salt flotation test. Methods described in Guidelines for Checking Fruit for SWD Larvae in the Field by Laura McDermott, available on Cornell Fruit Resources SWD pages, fruit.cornell.edu/spottedwing/.

Picture of a raspberry fruit with tiny breathing tube threads where an egg is inserted under the skin.
Tiny threads of the SWD egg breathing tubes indicate where an egg was laid in a raspberry. Two eggs were found in 40 fruits examined.

Pay attention to SWD -- look for symptoms of leaky fruit; flat, sunken, & dull spots or dimples on the fruit surfaces; or distorted & disintegrating fruit. Protect ripe and ripening fruit crops from infestation with an insecticide program.

Details about each County's sustained catch:

  • Orange: 6/14/2019, 23 females & 3 males, raspberry & gooseberrytotal 36
  • Columbia: 7/8/2019, 4 females & 1 male, tart cherry – total 5
  • Clinton: 7/9/2019, 3 females & 2 males, blueberry – total 5
  • Wayne: 7/9/2019, 3 females & 1 male, raspberry – total 4

The sustained catch report in Orange County was a month ago! This report slipped my attention, but it underlines that SWD has been found in many fruit plantings for upwards of a month now.

The sustained catch in Columbia County of only 5 SWD in the tart cherries after the prior week’s catch of 32 underlines the impact of an insecticide program on SWD populations and trap catch.

Refer to the insecticide quick guides online. Choose a material with excellent efficacy against SWD and an appropriate days-to-harvest interval.

SWD Insecticides for Berries, www.hort.cornell.edu/fruit/pdfs/swd/berry-insecticides.pdf

SWD Insecticides for Stone Fruit & Grapes, www.hort.cornell.edu/fruit/pdfs/swd/treefruit-grape-insecticides.pdf

Thank you for monitoring SWD in the Counties with sustained catch!

  • Andy Galimberti, CCE Eastern NY Commercial Horticulture Program (Clinton County)
  • Natasha Field, CCE Eastern NY Commercial Horticulture Program (Columbia County)
  • Nate Mengaziol and Laura McDermott, CCE of Orange County and Eastern NY Commercial Horticulture Program (Orange County)
  • Ryan Parker and Juliet Carroll, CCE NYS IPM Program (Wayne County)

Four SWD, 2 females and 2 males, were caught in traps set in a blueberry planting in Onondaga County on July 10, 2019. Traps were checked by Ryan Parker and Juliet Carroll, NYS IPM Program.

This completes first catch for all locations in the SWD Monitoring Network. We'll continue to report sustained catch and provide updated management information to keep you up-to-date on SWD.

SWD distribution map picture.
SWD distribution map for New York. SWD has been found in all the counties in the network, as of July 10, 2019. Counties in white don't have traps or reports in.

Yikes! After catching nothing last week... First catch had 26 SWD caught in four traps set in a blueberry planting in Tioga County — 15 females and 11 males. These traps are being monitored by Barb Neal, CCE of Tioga County and Shona Ort, CCE of Chemung County.

I'd say it's time to protect the crop at this location! We want to bring in a good crop and protect it. For comprehensive information on protecting blueberries from SWD, download and read the new IPM guide from the SWD IPM Working Group.

Spotted Wing Drosophila IPM in Blueberries
neipmc.org/go/swdpub2

Also, refer to the insecticide quick guide to augment the information in the above IPM guide.

A picture showing two male SWD on a blueberry.
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.
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