4 female SWD were caught the week ending July 15, 2017 in two traps set near some wild raspberries growing outside a blueberry planting. This is sustained catch at this location. Paul Hetzler, extension educator, St Lawrence County CCE, is monitoring these traps as part of a berry research project.
Although Paul expected to find more SWD this week, often SWD is slow to build up to large numbers, as has been the case this year. Single digit numbers of total SWD caught in the 2-4 traps set at a location is common in the first two weeks of trapping, with double digit numbers occurring in the third and fourth weeks.
In prior years, blueberry plantings in Central New York haven't had significant levels of infestation until early August, though this year this might occur by the end of July. Fruit can be monitored for infestation by sampling good quality fruit and screening it using a salt flotation assay.
SWD was confirmed caught on July 8, 2017 from traps set in a blueberry planting in St Lawrence County. 2 female SWD were caught in one of two traps. There are ripening 'Blue Ray', 'Duke' and 'Blue Crop' blueberry varieties in the field, but 'Patriot' is still green at this location.
These traps are being monitored by Paul Hetzler, extension educator, St Lawrence County Cornell Cooperative Extension, as part of his demonstration research on protected culture production of berry crops.
As blueberries ripen and SWD is caught in your area, sample fruit to check for SWD infestation with a salt flotation assay.
Make sure customers know to keep fruit refrigerated, and freeze, process or use fruit as soon as possible after purchase.
1 male SWD was caught June 29, 2017 in one of 6 traps set in a 300 acre preserve field research site that has no managed fruit plantings.
1 female SWD was caught July 6, 2017 in one of 7 traps set in a managed cherry orchard (tart and sweet). Harvest is underway at this orchard.
There are no SWD traps in the monitoring network set in Oswego County. These traps are being monitored by Dr. Peter Newell, Assistant Professor, Dept of Biological Sciences, Oswego State University of New York, Oswego, NY, who shared his findings with me. Gabrielle Solomon, undergraduate student working in his lab, services the traps and does the Drosophila identifications.
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.
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 Drosophilasuzukii. 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.
Dr. Greg Loeb’s entomology research program, Cornell University, Geneva, NY, has caught 3 SWD females in traps set on the edge of a blueberry planting that is adjacent to woods in Ontario County. This blueberry planting is often the site where Greg’s program catches SWD first. Traps were set out on May 31st and checked on June 7th, which indicates the SWD were caught sometime during that week. The good news is that the blueberry crop is not ripe and therefore not vulnerable to oviposition at this site.
This is the earliest that SWD has been caught in New York State since monitoring began in 2012. The mild winter that occurred in New York, with only one significant cold snap around February 14th, may have contributed to early arrival and overwintering success of SWD. Mild winters and early SWD arrival is the typical situation that is now found in Europe with this invasive insect.
Research by Dr. Anna Wallingford, a post-doctoral associate in Greg’s lab, and others is finding that SWD goes into reproductive diapause in the late fall during which time egg laying ceases and overwintering survivability increases. The traps used to catch these three females were baited with a fermenting lure that is being researched by a team at Rutgers the State University of New Jersey. This same team has research that is underway, on the female SWD caught in these fermenting lure traps, to determine if these early-arrival females are ready to lay eggs.
There is no doubt, the SWD season has begun in New York and it looks as if the 'mild winter early arrival' predictions may prove true. Please note: this finding won't show up on the SWD distribution map, because research trap sites aren't part of the 'map-reporting' monitoring network.
"The system worked extremely well. In 2014, with the 80 gram netting, at most, only 0.53 percent infestation occurred in a 10 week harvest season. Unsprayed berries without exclusion netting had as high as a 60% infestation level in one sampling period alone. In 2015, using the 80 gram netting, at most, a 0.37% infestation was found over a 5 week harvest season. Sprayed berries without exclusion netting had as high as a 20% infestation level in an individual sampling period. The netting held up through 3 severe thunderstorms and 2 hail storms and we refined our attachment system for large scale deployment of large pieces of netting.
This system has great potential for small scale, organic, and no-spray blueberry growers and I believe the system can be used by raspberry growers as well."
You can order the exclusion netting from Dale Ila Riggs, The Berry Patch, Stephentown, NY. For questions, contact her at email@example.com. Orders with Tek-Knit must be finalized this week.
If you've been considering protecting your berries from SWD with exclusion netting, read the report to see if this approach could work on your farm. Don't delay, contact Dale Ila to get the netting you need as part of her bulk order with Tek-Knit.
Seven females and three males were caught in an apple cider vinegar trap at a farm in Rensselaer county this week. Traps were collected on July 13, 2015 and are with the lure comparison research that Greg Loeb, Department of Entomology, Cornell University is leading. Traps are being serviced by Laura McDermott, Eastern NY Commercial Horticulture Program. The traps were in set in an Amelanchier hedgerow near strawberries. Amelanchier species are commonly known as shadbush, shadwood or shadblow, serviceberry, sarvisberry or sarvis, juneberry, saskatoon, wild pear, sugarplum or wild-plum, and chuckley pear. In nature, this genus hybridizes readily and species distinctions can be difficult.
One female SWD was caught in a trap collected on June 25, 2015 at a Schuyler County research site. The trap contained whole wheat fermenting bread dough as the lure and was located on the edge of a blueberry planting. (This site doesn't report to the SWD distribution map.)
The New York SWD distribution map reports will come from the NY monitoring network which has traps out in 29 Counties at 48 different sites. So far only Orange County and Wayne County traps in this network have caught SWD – a single female each.
People monitoring in the SWD network are with Cornell University’s College of Agriculture and Life Sciences and Cornell Cooperative Extension. Four traps are placed at each site, two within the crop, either raspberry or blueberry, and two on the edge of the crop, though some sites may have only two traps. Below is a table with details about the SWD network trap locations.
A single female was caught at a research site in Orange County using a baited Trécé trap, set during the week of June 15th-22nd by Peter Jentsch, entomologist, Hudson Valley Laboratory, Cornell University. The trap uses a combination lure incorporating both pheromone and kairomone—a feeding attractant. Jentsch examined red raspberry fruit from a 25-count-sample collected on Monday the 22nd (var. Caroline) and no ovipositional stings or egg breathing tubes were found. Read more on The Jentsch Lab blog.
These females are capable of laying eggs, so it is time to get set, get ready, and go protect your fruit crops. June strawberry harvest is winding down, so this crop may not need protection. Summer raspberry is showing ripe fruit now and will be at risk in 2015. Sweet cherry and tart cherry will be at risk, since they may ripen and be harvested over the next few weeks, consider what materials you have in your insecticide programs and make sure that SWD is covered.
The research comparing different lures for catching SWD early is ongoing at three locations in NY - comparisons are being done between a Trécé lure, a Sentry lure, a boosted lure from Trécé, the standard fermenting bread dough (used in the NY monitoring network), Cha Landolt synthetic lure, and apple cider vinegar alone. These research sites aren't included on the SWD distribution map, so don't be confused by Orange County still showing in gray for none found. This means there have been none found in the monitoring network sites in Orange County.