Brief Summary of Minutes of Annual Meeting

Meeting Agenda:

8:00-8:05 AM                Introductory Remarks, Address by Administrative Advisor Laura Lavine

8:05-8:20 AM                The salt test method: an efficient tool to monitor for spotted wing drosophila infestation in fruit (Lauren Diepenbrock, Steven Van Timmeren, Matt Bertone, Hannah Burrack and Rufus Isaacs)

8:20-8:35 AM                Group discussion on salt test method

8:35-8:50 AM                A semi-field bioassay protocol for assessing the effectiveness of field-aged insecticides against spotted wing drosophila (Steven Van Timmeren and Rufus Isaacs)

8:50-9:05 AM                Group discussion of semi-field bioassay methods

9:05-9:20 AM                Protocols for screening spotted wing drosophila field populations for insecticide resistance (Ashfaq Sial)

9:20-9:35 AM                Group discussion for protocols for insecticide resistance screening

9:35-10:35 AM             State impact statement reports poster session

10:35-10:50 AM           Sustainable spotted wing drosophila management in US fruit crops: Year 2 update (Hannah Burrack, Joanna Chiu, Kent Daane, Miguel Gomez, Larry Gut, Rufus Isaacs, Gregory Loeb, Cesar Rodriguez-Saona, Ashfaq Sial, Vaughn Walton and Frank Zalom) 

10:50-11:05 AM           Development and implementation of systems-based organic management strategies for spotted wing drosophila: An OREI project update (Ashfaq Sial, Rufus Isaacs, Matt Grieshop, Christelle Guédot, Kelly Hamby, Vaughn Walton, Mary Rogers and Hannah Burrack)

11:05-11:20 AM           Developing research strategies for spotted wing drosophila: Learning from the past and building for the future (Justin Renkema)

11:20-11:55 AM           Research priorities discussion

11:55-12:00 PM           Concluding remarks (elected a 2019 chair: Bill Hutchison UMN)

Brief Summary of Annual Meeting Minutes:  

1. The Salt Test Method (Lauren Diepenbrock): The salt test method was published in the Journal of Integrated Pest Management in 2017 (available on the SCRI website). The article includes ID information to key larvae by instar. The salt method is recommended because it is transportable and can be done at the farm. Materials are inexpensive and easy to obtain.

     Discussion: 

• Can we make a youtube video demonstrating this method?
  1. Yes!
• Are salt and sugar water methods comparable? Has not been specifically tested.
  1. Salt may be preferable to sugar because it is less sticky and less attractive to ants, but it is easier to rear larvae from sugar solution. Salt solution can kill larvae, but sometimes see live ones even after 1 hr in salt solution. There is not yet knowledge on a minimum time in the solution, overall no data on time soaking versus emerging larvae.
  2. It is easier to see larvae if they are still moving.
• Does this method work for all fruit hosts?
  1. Salt test method does not get eggs out of caneberries.
  2. This method has worked in strawberries but could benefit from optimization
  3. Many labs use the Freezer method for strawberries, some sugar method, some salt. No direct comparisons between methods
  4. Large container and sugar water method used for cherries, does the salt test method scale up for cherries?
• What type of fruit should be collecting in the field for monitoring?
  1. Market ripe fruit demonstrates consumer detectable pressure
  2. Overripe fruit might capture overall pest pressure earlier
  3. Overripe fruit might also increase number of non-target larvae
  4. Can ID using key in new publication, also eggs of Zaprionus indianus have 4 spiracles that are usually visible on the surface of the fruit, this species becoming the most common non-SWD Drosophilid in captures

2. Semi Field Bioassay Method: Methods for this bioassay were published in Crop Protection in 2013, and described in detail here. Suggestions for setting up the bioassay: use the fume hood, fill water pick with a syringe to keep cup dry, use plenty of glue to ensure a good seal, a diet dish helps improve control mortality. When clipping foliage, location (height and interior/exterior) matters. Also collect fruit for a negative control (measure background infestation). Push shoot into the water pick, clipping leaves if necessary. Berries can be plucked off and put in a berry holder. To the bioassay cups, add 6F and 6M flies, 2-5 days old. Keep at 25C and 75% RH to make sure the controls don’t die for 7 days. Assess fruit for larvae using the salt test method. 

     Discussion:

• Concern that diet dish is an alternative oviposition substrate that can reduce number of larvae laid in test fruit, alternatives?
  1. Use a paper diet (liquid food dried on paper) or dry sugar and yeast
  2. Offer a food source that is not an oviposition substrate (Dry powder of 4 parts white sugar, 1 part yeast hydrolyzate, pulverize with a pestle).
  3. For diet, can soak strip of filter paper in yeast, sugar, water mix and moist cotton ball in a 1 oz cup.
  4. Some groups do not use diet at all, is included to improve control survivorship
• Cheaper option to add SWD to bioassays instead of CO2 pad:
  1. Aspirate live flies into a 50 ml plastic tube with a flug in the bottom. Knockout in freezer, gently knock into the bioassay container.
• Other Modifications to the approach
  1. Modified cups with diet plugs to facilitate moving flies in and out.
• General notes/comments about the approach
  1. Check the bottom of the container for escaped larvae
  2. Use very clear containers not slightly opaque, carefully and slowly count individuals
  3. Use a humidity controlled chamber, or a salt concentrate solution to increase humidity, maybe a humidifier, especially if control mortality is high
• When do you collect the foliage/fruit?
  1. Some labs wait until REI is over
  2. Most often just wait 24 hours
  3. For far field sites, collect fruit right after spraying while wearing PPE
• Foliage assays with non-blueberry hosts
  1. For blackberries (and maybe cherries) you can use less leaves.
• How does this assay compare to field infestation?
  1. Has not be quantified
• Alternatives to sharp mesh berry holders:
  1. 1 oz deli cup used to put fruit in instead of the mesh, be careful of moisture that can collect in bottom of the cup

3. Protocols for evaluating SWD resistance: Stock solutions are made with water or acetone diluent. Using 20 ml scintillation glass vials, add 1 ml of solution and coat all surfaces by shaking. Only label lids so you can see all of the flies through the vial. Let vials air dry. Add 5F, 5M to the vials, assess after 6 hours. Count alive, moribund, and dead. So far, no populations are significantly deviating from baseline resistance, but we should continue to proactively monitor resistance development. Rapid resistance screening protocol was developed using a diagnostic dose of LC99x2.

     Discussion:

• Best way to address moribund flies?
  1. Evaluating after only 6 hrs so some slower acting compounds result in moribund rather than dead flies at this time, but moribund usually die if you keep them for longer
  2. Moribund flies are probably not going to be dispersing or ovipositing so for the sake of insecticide efficacy we can count them as “dead”
  3.  
• Addressing problems with control mortality (especially male flies):
  1. Don’t knock out the vials too early and then store them, they will die
  2. Really require high humidity to reduce control mortality, both where they’re loaded into the vials and also where the vials are stored
  3. Room humidifier can help humidity, saturated salts within growth chambers
  4. Short water wick included in the vials? This has been tried by putting a wick through the lid but it didn’t significantly improve control mortality and caused additional issues
  5. Only partially closing the lid or using mesh closures so that there is better air exchange with a humidified growth chamber might help
  6. Low humidity doesn’t seem to be a problem in all assay locations (CA doesn’t have much control mortality in their assays), perhaps a regional population effect?
• General comments about the protocol
  1. Scintillation vials are cheap enough that they can be rinsed and disposed of, most groups do not re-use them
  2. Rapid resistance screening dose of LC99x2 is a good option if you can’t get enough flies to do a full dose response line
  3. This approach was developed to be a very low input option so that county agents and others could use the assay in the field
  4. Bioassay could be a best-case scenario since light sources in growth chamber often do not have the UV light that breaks down insecticides in the field
• How long before hand can vials be stored?
  1. Most commonly only store them for 24-48hrs in a dark place
  2. Some groups have stored them for ~1.5 months in a dark fume hood and the assays seem to run fine after this storage period
• Figures presented seem as if Spinetoram dose-response lines are slowly changing, is this what we’re seeing?
  1. Probably seeing the effect of the slower time to kill for Spinetoram
  2. Moribund vs. dead flies and their interpretation probably contributing to the slope of the line
1. Likely a dilution of resistance alleles from susceptible populations
2. Populations in alternate hosts and during times of the year where they are not being sprayed
3. Could test levels of resistance from populations collected in the middle vs. the edge of the field to see if this population mixing is occurring at a field scale Why aren’t we seeing more resistance?

4. SCRI Project Update: Multi-state collaborators participating in SCRI Project # 2015-51181-24252 are working on the following objectives:

• Obj 1.1: Develop and implement grower-scale best management practices.
• Obj 1.2: Build tools to measure SWD impact, predict losses, and suggest mitigation strategies.
• Obj 1.3: Provide stakeholders with results, applications, and interpretation of project activities. Surveys were administered in 2016 and 2017, greater than 330 respondents each time. Also hosted the first webinar.
• Obj 2.1 Field validate and implement population models.
• Obj 2.2 Determine sources of SWD populations between and during growing seasons.
• Obj 2.3 Develop monitoring tools that accurately estimate SWD populations.
• Obj 3.1 Reduce reliance on insecticides in management programs.
• Obj 3.2 Develop insecticide resistance detection, minimization, and management strategies. Developed methods to determine baseline susceptibility rates (van Timmeren et al. 2017).
• Obj 3.3 Discover natural enemies capable of reducing SWD populations. International prospecting for new agents, testing to enable field releases. (Biondi et al. 2017 and Kacar et al. 2017).
• Obj 3.4 Reduce infestation rate in fruit post-harvest. Optimal sorting tools in blueberries to determine whether they can detect infested fruit.
• Obj 3.5 Develop genetic management tactics.

5. OREI Project Update: Update: Multi-state collaborators participating in OREI Project # 2015-51300-24154 are working on the following objectives:

• Obj 1.1 Determine optimal SWD attractants for trapping and killing. YS+Scentry best caught flies earliest and most flies, YS 2^nd best for most flies.
• Obj 1.2 Determine the role of physiology on SWD response to semiochemical attractants. Virgins are more responsive than mated flies.
• Obj 1.3 Develop prototype attract and kill strategies.
• Obj 1.4. Evaluate how devices function under field conditions. SWD temporal and special usage of and dispersal among crops and non-crop hosts. Year round more flies are in the woods, during the heat of summer trap captures decline.
• Obj 2.1 Evaluate efficacy of environmental manipulation strategies in the canopy. We can increase light penetration (and hopefully manipulate the climate) with heavy pruning.
• Obj 2.2 Evaluate efficacy of environmental manipulation strategies on soil habitat. Temperatures above the weedmat are higher than those below.
• Obj 2.3 Feasibility of insect netting to exclude SWD and increase crop quality and yield. Exclusion netting can keep SWD out, and high tunnels reduce infestation.
• Obj 3 Evaluate effectiveness of current and new organic insecticidal chemistries against SWD. Entrust seems to be the only product that works.

6. Developing Research Strategies for SWD (Research in Renkema lab at UF): Orius+ nematodes may be a good biological control community in terms of commercially available biological control products in strawberries. There is no real complementarity or interference, predatory identity is more important than composition. Conservation biological control: Strips of sweet alyssum and Spanish needles evaluated. Alyssum may be repellent- there was less SWD in bowl traps near flowers. A potential repellent chemical from flowers showed a reduction in larvae per berry and may repel adults too. In Florida strawberries, winter morphs are found in traps in north FL than central FL. In north FL, there are more nights below freezing than central FL.

     Discussion:

• Is SWD an economic problem in FL strawberries? In some cases, yes.
• Flowers are thought to be repellant rather than cause object recognition issues because flies leave rather than not recognizing fruit.

 7. Research and Extension Priorities Discussion

• Extension Priorities: Best Management Practices to share with growers.
• Research Priorities:
1. Management: N/A
1. Long distance dispersal and movement between habitats.
2. Environmental predictors of SWD appearance and abundance. (Dalila is doing some of this in OR and would like to collaborate).
3. Microbes in SWD: pathogen selection/screening.
4. How do adults use resources as they move in and out of the fields with other habitats?
5. Winter morphs captured through January but then can’t find them in early spring, instead find summer morphs in June. Is there a missing interim host? What are they doing during this time?Biology and Ecology Priorities

8. Elect a 2019 Chair

• Thanks to Bill Hutchison from the University of Minnesota for agreeing to be the 2019 WERA 1021 chair and the 2018 vice-chair.

Objective 1: Improve our understanding of SWD populations and develop tools to accurately predict SWD risk.  

In 2016-2017, we made considerable strides toward understanding SWD biology and behavior, including insights useful for monitoring. Attracticidal spheres, pouches impregnated with pesticide, and traps were found to be effective for trapping and/or killing SWD. Although a good metric for monitoring, these were not found to be effective for management, as high trap catches did not correlate to reduced population sizes or infestation. It was discovered that counting only males in traps is a reliable method for monitoring. Male SWD are morphologically distinctive from other Drosophila spp., so the ability to accurately estimate population density based on this metric saves time and does not require specialized skills. Gravid females are attracted to raspberry baits, whereas unmated and starved SWD are attracted to fermentation lures, so use of each lure type may be of temporal or spatial importance. Trapping studies also demonstrated the importance of wild and unmanaged landscapes as refuge, especially for overwintering or when crop hosts are unavailable. Wooded and/or pine-dominated edges are especially attractive. In field studies, flies were found to travel up to 100m, and marked flies were found in traps 7.5 acres away from their release site. On a flight mill, an individual could travel up to 1.2 miles. Information about dispersal and preferred habitats can aid in the creation of tools that predict SWD risk. 

Objective 2: Optimize use of pesticides to reduce reliance upon them and disruption of beneficials. 

Growers find insecticide application expensive and labor intensive, especially in small fruits where they rarely applied sprays prior to SWD infestation. Many growers are considering abandoning late-season varieties, as these require more pesticide application. Insecticide studies from multiple states and in multiple cropping systems demonstrated that insecticide efficacy varies widely, but overall, the need for a well-designed rotation of products is clear. Entrust, recognized as one of the more efficacious organic products considered, was found to lose efficacy at 5 days after treatment. Additionally, dense foliage can make spays ineffective, especially in the center of the canopy where SWD often reside. A higher carrier volume may aid in better spray coverage. A number of adjuvants were considered, but generally did not improve the insecticide, with the exception of sugar in some cases and NuFilm P in some cases. Adjuvant responses vary significantly between states/experiments. 

Objective 3: Develop non-pesticide based tactics for SWD management and evaluate sustainable SWD management programs to provide best management practices for SWD.  

Many groups worked to develop non-pesticide based management options in 2016-2017. An effective but labor-intensive strategy is to harvest more often. High tunnel exclusion was also beneficial but may be difficult to scale up. A multi-state collaboration on classical biological control demonstrated the challenges of this strategy. Natural parasitism rates are very low in the US, and candidate parasitoids failed to parasitize SWD in the laboratory. Work in this area is ongoing to identify efficacious candidate organisms. It is likely a complement of parasitoids that utilize different life stages (larval stage, pupal stage) is necessary for effective biological control. Microclimate manipulation may be possible in the canopy if pruning is heavy enough to affect light penetration. Increased temperatures or decreased relative humidity in the canopy may affect SWD ability to survive, develop, and reproduce. Floor management using mulches in blueberries may also impact SWD survival. Temperatures are higher above the mulch than below, and this is especially true when using a black fabric weedmat. The weedmat also acts as a physical barrier for larvae or pupae to get below the mulch where conditions are more favorable. 

Objective 4: Coordinate grant-funded research and extension efforts to minimize redundancy and ensure knowledge transfer.  

Zero tolerance for infestation and the increased financial and labor inputs required to manage SWD reduces growers’ profits and threatens U.S. fruit production. It is critical to continue to engage and inform growers as we learn more about this pest. In addition, we must share our results with other scientists and extension personnel who need to deliver relevant up-to-date research based information to their stakeholders. This year, many states spearheaded monitoring on a large scale to inform producers of SWD risk and help with timing of management. Communication of our findings was widespread and used several formats, including extension presentations and field days, journal publications, farm visits, media presentations, and scientific conferences. Some states reported survey results that highlight the impacts of this work. For instance, in Michigan, 92% of survey respondents used information provided about SWD to make management decisions, and 76% altered their insecticide programs based on recommendations. In Maryland, 65% of respondents expected information shared at extension meetings to benefit their operations, and 60% intended to share what they learned with other growers. At our 2017 meeting we were able to peer review 3 research protocols, update each other on collaborative research efforts, and start working towards research and extension priorities. This will facilitate SWD research and extension around the country and encourage collaborations to pursue future grant funding for SWD work. Collaboration is also evident in our impacts and publications, with many states contributing.

WERA 1021 Publications:

Peer Reviewed Manuscripts:

1. Avanesyan, A., Jaffe, B.D., and C. Guédot (2017) Isolating spermatheca and determining mating status of the invasive spotted wing drosophila, Drosophila suzukii: a protocol for tissue dissection and its applications. Insects: Special issue “Invasive Insect Species”. 8(1), 32; doi:10.3390/insects8010032. Invited paper.
2. Becher, P.*, and Hamby, K.A. 2016. Current knowledge of interactions between Drosophila suzukii and microbes, and their potential utility for pest management. Journal of Pest Science. Invited Review. Special Issue: Spotted wing Drosophila DOI: 10.1007/s10340-016-0768-1
3. Biondi, A., X. Wang, J.C. Miller, B. Miller, P.W. Shearer, L. Zappala, G. Siscaro, V.W. Walton, K.A. Hoelmer, and K.M. Daane. 2017. Innate olfactory responses of Asobara japonica toward fruits infested by the invasive spotted wing drosophila. Journal of Insect Behavior 30(5):495-506.
4. Fanning P, Grieshop M, Isaacs R. (2017) Efficacy of biopesticides on spotted wing drosophila, Drosophila suzukii Matsumura in fall red raspberries. Journal of Applied Entomology doi: 10.1111/jen.12426
5. Farnsworth, D.*, Hamby, K.A., Bolda, M., Goodhue, R., Williams, J., and Zalom, F. 2016. Economic analysis of revenue losses and control costs associated with the spotted wing drosophila (Drosophila suzukii (Matsumura)) in the California raspberry industry. Pest Management Science. DOI: 10.1002/ps.4497
6. Hall, M., Loeb, G., Wilcox, W. 2017. Sour rot: etiology, biology, and management. Internet Journal of Enology & Viticulture, 2017, N. 6/1.
7. Hamby, K.A.*, Bellamy, D.E., Chiu, J.C., Lee, J.C., Walton, V.M., Wiman, N.G., York, R.M., and Biondi, A. 2016. Biotic and abiotic factors impacting development, behavior, phenology, and reproductive biology of Drosophila suzukii. Journal of Pest Science. Invited Review. Special Issue: Spotted wing Drosophila DOI: 10.1007/s10340-016-0756-5
8. Haviland, D.R.*, Caprile, J.L., Rill, S.M., Hamby, K.A., and Grant, J.A. 2016. Phenology of spotted wing drosophila in the San Joaquin Valley varies by season, crop, and nearby vegetation. California Agriculture 70(1): 24-31. DOI: 10.3733/ca.v070n01p24
9. Hietala-Henschell K., Pelton E., and Guédot C. (2017) Susceptibility of aronia (Aronia melanocarpa) to Drosophila suzukii (Diptera:Drosophilidae). The Journal of the Kansas Entomological Society (in press)
10. Holle, S.G., E.C. Burkness, T.M. Cira, & W.D. Hutchison. 2017. Influence of previous fruit injury on susceptibility to spotted wing Drosophila (Diptera: Drosophilidae) infestation in the Midwestern United States. J. Entomol. Sci. 52(3):207-215. http://www.bioone.org/doi/abs/10.18474/JES16-07PT.1
11. Huang, J., L.J. Gut, and M. Grieshop. 2017. Evaluation of food-based attractants for spotted wing drosophila, Drosophila suzukii (Diptera: Drosophilidae). Envin Entomology. 46:878-884.
12. Kacar, G., X. Wang, A. Biondi, and K.M. Daane. 2017. Linear functional response by two pupal Drosophila parasitoids foraging within single or multiple patch environments. PLOS ONE 12(8).
13. Kirkpatrick, D.M., P.S. McGhee, LJ Gut, and JR Miller. 2017. Improving monitoring tools for spotted wing drosophila, Drosophila suzukii. Entomol. Exp ed Appl. 164 (in press)
14. Leach, H. J. Wise, and R. Isaacs (2017b). Reduced ultraviolet light transmission increased insecticide longevity in protected culture raspberry production. Chemosphere, doi: 10.1016/j.chemosphere.2017.09.086
15. Leach, H., Moses, E. P. Fanning, and R. Isaacs (2017a). Rapid harvest schedules and fruit removal as non-chemical approaches for managing spotted wing drosophila (Drosophila suzukii) in red raspberries. Journal of Pest Science, doi:10.007/s10340-017-0873-9.
16. Renkema, JM, Iglesias L, Bonneau P, Liburd, O. Trapping system comparisons for and factors affecting populations of Drosophila suzukii and Zaprionus indianus in Florida strawberry. Pest Management Science.
17. Rice, K.B., B.D. Short, and T.C. Leskey. 2017. Development of an attract-and-kill strategy for Drosophila suzukii to (Diptera: Drosophilidae): evaluation of attracticidal spheres under laboratory and field conditions. Journal of Economic Entomology 110: 535-542.
18. Rice, K.B., B.D. Short, S.K. Jones, and T.C. Leskey. 2016. Behavioral response of Drosophila suzukii to (Diptera: Drosophilidae) to visual stimuli under laboratory, semifield and field conditions. Environmental Entomology 45: 1480-1488.
19. Rice, K.B., S.K. Jones, W.R. Morrison, and T.C. Leskey. Spotted wing drosophila prefer low hanging fruit: insights into foraging behavior and management strategies. Insect behavior (accepted).
20. Rogers, M., E.C. Burkness & W.D. Hutchison. 2016. Evaluation of high tunnels for management of Drosophila suzukii in fall-bearing red raspberries: Potential for reducing insecticide use. J. Pest Science. 89(3): 815-821. https://doi.org/10.1007/s10340-016-0731-1.
21. Stockton, DC & Loeb, GM (2017). Refining the use of automatic sprayers in a push-pull system of oviposition disruption against Drosophila suzukii. (In prep)
22. Van Timmeren, S. Diepenbrock LM, Bertone MA, Burrack, HJ, Isaacs R (2017a). A filter method for improved monitoring of Drosophila suzukii (Diptera: Drosophilidae) larvae in fruit. Journal of Integrated Pest Management doi: 10.1093/jipm/pmx019.
23. Van Timmeren, S. Mota-Sanchez, D., Wise, JC, and Isaacs (2017b). Baseline susceptibility of spotted wing drosophila (Drosophila suzukii) to four key insecticide classes. Pest Manag. Sci. (accepted) Author Manuscript doi:10.1002/ps/4702.
24. Wallingford, A., Lee, J, Loeb, G. 2016. The influence of temperature and photoperiod on the reproductive diapause and cold tolerance of spotted-wing drosophila, Drosophila suzukii (Matsumura). Entomologia Exerimentalis et Applicata, 159:327-337. DOI: 10.1093/jee/tow116.
25. Wallingford, A.K., Cha, D.H., and Loeb, G. 2017. Evaluating a push-pull strategy for management of Drosophila suzukii Matsumura in red raspberries. Pest Management Science, DOI: 10.1002/ps.4666.
26. Wallingford, A.K., Cha, D.H., Linn, C.E., Wolfin, M., and Loeb, G. 2017. Robust manipulations of pest insect behavior using repellents and practical application for integrated pest management. Environmental Entomology, doi: 10.1093/ee/nvx125.
27. Wiman, N.G., Dalton, D.T., Anfora, G., Biondi A, Chiu, J.C., Daane, K.M., Gerdeman, B., Gottardello, A., Hamby, K.A., Isaacs, R., Grassi, A., Ioriatti, C., Lee, J.C., Miller, B., Rossi Stacconi, M.V., Shearer, P.W., Tanigoshi, L., Wang, X., and V.M. Walton*. 2016. Drosophila suzukii population response to environment and management strategies. Journal of Pest Science. Special Issue: Spotted wing Drosophila DOI:10.1007/s10340-016-0757-4

Extension Publications:

1. Alston, DG, LR Spears, C Nischwitz, and C Burfitt. 2016. Invasive fruit pest guide for Utah: insect and disease identification, monitoring, and management. Utah Plant Pest Diagnostic Laboratory and USU Extension.
2. Arsenault-Benoit, A., C. Taylor, B. Butler, and K. Hamby. 2017. Cultural controls for SWD management in blueberries and raspberries. University of Maryland Extension Vegetable and Fruit News: October 27, 2017.
3. Arsenault-Benoit, A., C. Taylor, B. Butler, and K. Hamby. 2017. Evaluating blueberry mulching practices on survival of spotted wing drosophila. University of Maryland Twilight Tours, WMREC August 17, 2017 and WyeREC August 2, 2017
4. Fraver, C., and Loeb, G. 2016. Can monitoring of adult SWD provide sufficient advanced warning? NYS Berry Grower's Association Newsletter, 2016 Issue, March 2016, p 1-3.
5. Hamby, K.A., and C.S. Swett. 2016. Partners in crime? Preliminary investigations into the interactions between SWD and fruit rots in fall red raspberries. The Bramble 31(1) Spring 2016.
6. Lewis, M., B. Butler, and K. Hamby. 2017. Optimizing carrier water volume for enhanced spray coverage in brambles. University of Maryland Twilight Tours, WMREC August 17, 2017 and WyeREC August 2, 2017.
7. Lewis, M., Butler, B., and K. Hamby. 2016. Optimizing carrier water volume for enhanced spray coverage in raspberries. University of Maryland Extension Vegetable and Fruit News: October 21, 2016 7(6): 24-27.
8. Michigan SWD Management Guide for cherries (2017 update)
9. MN Department of Agriculture Fruit IPM Newsletter (2-3x monthly)
10. Petran, A. and M. Rogers. 2017. Pruning and mulching for control of spotted wing drosophila: effects on fruit marketability and infestation. Am. Society for Horticultural Science, Sept. 19-22, Waikoloa, HI.
11. Riggs, D., Loeb, G., Hesler, S., and McDermott, L. 2016. Using insect netting on existing bird netting support systems to exclude spotted wing drosophila (SWD) from a small scale commercial highbush blueberry planting. NY Fruit Quarterly 24: 9-14.
12. Spears LR, C Cannon, DG Alston, RS Davis, C Stanley-Stahr and RA Ramirez 2017. Spotted wing drosophila (Drosophila suzukii). Fact Sheet ENT-187-17. Utah Plant Pest Diagnostic Laboratory and USU Extension.
13. Spears, LR, R Davis, DG Alston, and RA Ramirez. 2016. First detector guide to invasive insects: biology, identification, and monitoring. Utah Plant Pest Diagnostic Laboratory and USU Extension.
14. Taylor, C. Butler, B., and K. Hamby. 2016. If you can't take the heat, stay out of the mulch: How mulching practices affect spotted wing drosophila survival in blueberries. University of Maryland Extension Vegetable and Fruit News: October 21, 2016 7(6):1-3.
15. Wallingford, A. and Loeb, G. Spotted wing drosophila winter biology. 2016. NY Fruit Quarterly. NY Fruit Quarterly 24 (3): 11-13.
16. Wallingford, A., and Loeb, G. Spotted wing drosophila winter biology. 2016. NYS Berry Growers Association Newsletter, 2016 Issue 2, April 2016, p 1 -3.