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Two male SWD were caught in a trap set on the edge of a blueberry planting on June 27, 2017 in Steuben County. The blueberries at this site are mostly green, but beginning to ripen. Traps at this site are being monitored by Stephanie Mehlenbacher, extension educator with Steuben County Cornell Cooperative Extension.

Unripe blueberry fruit is too hard for SWD to lay eggs in and doesn't warrant treatment with insecticide.

It will be important to take steps to manage SWD in your berry crops this year. Here are some resources:

Sustained catch (two weeks in a row catching SWD) was reported on June 26 and 27, 2017, in several counties: Albany, Rennselaer, Saratoga, Schuyler and Washington. Reports have come in from Annie Mills, field technician with Laura McDermott and the Eastern NY Commercial Horticulture Program and from Taylere Herrmann and Nicole Mattoon with me in the NYS IPM Program.

Specific findings:

Albany County - 10% ripe summer raspberries at the site and 52 SWD caught in 4 of 4 traps.

Rensselaer County - 31 SWD caught at this site in 3 of 4 traps.

Saratoga County - blackberries are still unripe at this site, but nearby sweet cherries are coloring up. 2 female SWD caught.

Schuyler County - summer raspberries are ripe at this site and 4 SWD caught in 3 of 4 traps set in that crop. At this farm, first catch also was found in the traps set in blueberries - 4 SWD females caught in 3 of 4 traps.

Washington County - most blueberries at this site are still just starting to color, but one variety is at about 25% blue. 15 SWD caught in 3 of 4 traps.

Examine your caneberry plantings for conditions that promote SWD infestation and take steps to eliminate them. Although we cannot change the weather, we can alter conditions in the planting to reduce the cool, dark, humid areas preferred by SWD. Pruning and training systems can help maintain an open canopy to increase sunlight and reduce humidity. This will make plantings less attractive to SWD, will reduce SWD activity, and will improve spray penetration and coverage.

Bumblebee pollinating pruned and trellised raspberry.

Pruning tactics for caneberries (raspberries and blackberries) have been developed to achieve excellent fruit yield and open the canopy. Knowing different pruning strategies will help you manage SWD. Added benefits include improved fruit color and flavor promoted by sunlight, easier picking by workers and customers, and easier weed management.

Caneberries (brambles) grown in the Northeast include red and black raspberries and blackberries, all are susceptible to SWD infestation. However, fruiting season differs among cultivars, which influences the risk of infestation.


  • Summer bearing varieties develop berries on floricanes that grow the prior year and overwinter. Fruit ripens and is harvested in early to mid-summer, prior to SWD population buildup, lowering the risk of infestation.
  • Fall bearing varieties develop berries on primocanes that grow, flower, and fruit in the same year. Fruit ripens and is harvested in late summer and early fall when SWD populations are high and risk of infestation is extreme.
  • Plants developing berries on floricanes and primocanes haven’t had floricanes removed after fall fruiting. Fruit ripens and is harvested from early to mid-summer on the floricanes and from late summer to early fall on the primocanes. The risk of SWD infestation will be low early in the harvest season and will increase as the summer progresses and the SWD population builds up.

Pruning suggestions for summer bearing varieties
Summer raspberries – maintain 4-5 healthy floricanes per foot of row.
Blackberries – maintain 3-4 healthy floricanes per foot of row.
Black raspberries – maintain 6-8 floricanes per hill.
Everbearing – maintain 4 primocanes and 4 floricanes per foot of row.

Floricanes should be held upright with a trellis to facilitate spray coverage and air circulation. Holding fruiting canes to the outside on a V-trellis will keep them to the outside of the growing primocanes and facilitate spray coverage and harvest.

Prune out the smallest primocanes beginning when they are 12 to 18 inches high to select and keep the biggest and best canes. Keep a few more than the suggested cane density per foot of row or per hill. Begin removing spent floricanes in July along with any late emerging primocanes. In November, laterals on black raspberry and blackberry primocanes can be cut back to 3 or 4 buds.

Pruning suggestions for fall bearing varieties
Maintain 4-6 primocanes per plant on a trellis.

Encourage early fruiting by placing row covers over the row after mowing in the spring. Remove the row covers when the primocanes are 18 inches tall. This will bring on flowering about two weeks early and help avoid or minimize SWD damage.


Nourse, N. 2015. Raspberry pruning timeline. Nourse News. Spring:2-3.

Pritts, M. 2013. Horticultural strategies for living with SWD. New York Berry News 12(10):1-2.

Two female SWD were caught in a summer raspberry planting on June 26, 2017, one each in a trap set on the edge and a trap set within the planting. About 40% of the fruit at this location is showing color and ripe for picking.

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

These traps are being monitored by Nicole Mattoon and Taylere Herrmann, NYS IPM Program field and summer technicians, respectively.

At this location, given the crop is ripe and ripening and the finding of SWD, it is time to begin to protect the crop with insecticides.

At two monitoring sites in Ulster County, SWD was caught in the week ending June 21, 2017. In summer raspberry at one site, 6 SWD (4 females and 2 males) were caught in two traps within the crop and 7 SWD (5 females and two males) were caught in two traps on the edge of the planting — total 13 SWD.

Four female SWD, as seen through a dissecting microscope, that were caught in a Scentry trap. The inset in the middle is a close-up of the females ovipositor.

The other site is small and the four traps are distributed between raspberry and blueberry. Interestingly, SWD weren't caught in the traps set in the blueberries, while in the summer raspberries 18 SWD were caught. 5 females and 2 males in two traps within the crop and 9 females and 2 males in two traps on the crop edge.

This report comes from Jim O'Connell, extension educator, Ulster County Cornell Cooperative Extension.

With reports of sustained catch and double digit SWD being caught in summer raspberry locations, it is crucial to plan your SWD management tactics for the raspberry season and, if raspberries are ripe, begin to protect fruit with insecticides.

Many reports are also being updated to the NY State distribution map, hosted by the Eastern Spotted Wing Drosophila Volunteer Monitoring System, The University of Georgia - Center for Invasive Species and Ecosystem Health. Please note - Suffolk County, Long Island has caught SWD, though the map indicates gray (as of June 27, 2017). All other NY Counties showing gray have not yet caught SWD.

At two sites in Tioga County, SWD has been caught two weeks in a row as of June 20, 2017, indicating established populations. Numbers caught are still low. Four SWD, 1 female and 3 males, in one trap set outside a high tunnel of raspberries. Three SWD, 2 female and 1 male, in one trap set on the edge of an open-grown raspberry planting.

Tiny threads of the SWD egg breathing tubes indicate where an egg was laid in a raspberry.

These traps are being maintained by Margaret Ball, extension educator, Tioga County Cornell Cooperative Extension. The insects caught are being sorted and identified by Nicole Mattoon and Taylere Herrmann in my fruit IPM program.

In our hummingbird research site, SWD has been caught in traps. This occurred during the week ending June 22, 2017. We have 36 traps set at this location, which is a very high number of traps. Although not representative of a typical SWD monitoring site, given the number of reports coming in from other counties, we thought it best to report this finding. Hummingbirds have arrived at our research plot this year, as well.

It is still unclear what impact the hummingbirds are having in the raspberry planting. Last year's drought significantly impacted our ability to monitor fruit infestation because fruit dried up and flowering ceased.

The hummingbird feeders do attract hummingbirds into the raspberry planting. They spend time at the feeders, as well as within the planting. They have been observed flying from the feeders into the planting and flying up from the planting to the feeders.


Six female SWD were caught in traps checked on June 21, 2017 set in a raspberry planting in Wayne County. There are some ripe fruit present in the planting at this time. These traps are being monitored by Nicole Mattoon, field technician, and Taylere Herrmann, summer technician, with Juliet Carroll's program, NYS IPM Program, Cornell Cooperative Extension.

The impact of SWD infestation on raspberry fruit in late summer can be severe. Get this fruit out of your planting to reduce SWD population build up.

It is looking like it may prove to be an early and challenging year for managing SWD in berry crops, with summer raspberries at risk. Please review SWD management guidelines and read through the SWD blog, Protecting crops from SWD infestation.

Three female and one male SWD were caught the week ending June 23, 2017 in two traps set on the edge of a blueberry planting in Rensselaer County. The two traps set within the crop did not catch SWD. The blueberries are not yet ripe, though the 'Duke' are about 10 days from picking.

This information is from Annie Mills, field technician, and Laura McDermott, extension educator, with the Eastern NY Commercial Horticulture Program, Cornell Cooperative Extension.

Checking SWD specimens with hand lens at the Albany workshop.

For review:

SWD monitoring

SWD management

SWD insecticides for berries

SWD on Cornell Fruit Resources

One female SWD was caught the week ending June 23, 2017 in a trap placed at the edge of a blueberry planting in Washington County. This information is from Annie Mills, field technician with Laura McDermott, Eastern NY Commercial Horticulture Program, Cornell Cooperative Extension.

Many reports are coming in of first catch of SWD. Make sure your berry planting row middles are kept mowed, weeds are kept down within the rows, and plantings are pruned to allow sunlight penetration and good air circulation. Monitor the planting for ripening and ripe fruit. The berries at this site were close to being ripe last Monday, June 19. The majority of the planting is at late green fruit with just a few clusters/plants at fruit coloring.


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