2023 SCRI NIFA Sustainable SWD Management Webinar

Webinar announcement.

Ohio growers have been battling spotted wing Drosophila in caneberries, blueberries, strawberries, peaches and grapes since 2011. For those growers still in the fight and interested to learn about recent advances in biocontrol of this pest, consider registering for the webinar below. These world class researchers will provide the latest information available on the topic.

We are excited to announce the 2023 SCRI NIFA Spotted-Wing Drosophila Management Team Webinar on Monday, December 4th, 2023 at 12:00pm EST. This one hour webinar, titled “Advances in Biological Control for Management of Spotted-Wing Drosophila” will provide updates on biological control efforts. Researchers will present recent findings as well as highlight advancements in biological control strategies to manage spotted-wing drosophila.

To register for this webinar, please follow this link: https://zoom.us/webinar/register/WN_z6DZY3p_RIGr4So-zhJXaQ

We look forward to you attending our webinar!

OSU Extension Bi-Weekly Fruit & Vegetable Report – October 17th, 2023

The OSU Extension Fruit & Vegetable Report is written/published collectively by OSU Extension staff across the state. 

Biological Soil Health

When it comes to supporting healthy soils, the physical and chemical aspects of soil quality are often highlighted. However, the importance of biological activity and diversity, and how it influences soil structure and chemical properties (pH, electrical conductivity, etc.), is becoming increasingly appreciated in modern farming. As we discover more about the different microbe-microbe and microbe-plant interactions unfolding in the soil habitat, we can create better farming practices that optimize crop health and soil quality.

Three areas of soil health: physical, chemical, and biological. Image courtesy of University of Massachusetts. 

The source of and final destination of all soil life is soil organic matter (SOM). SOM consists of biological material in the soil, derived from plants, fungi, animals, and other organisms, that are in various stages of decomposition. Certain forms of SOM break down quickly and provide nutrients for crop use, others are more stable (i.e. inaccessible to microbial decay) and contribute to aggregate stability and tilth. A SOM content of 5% in mineral soils is considered high; in muck soils, SOM can be as high as 80%. Conservation ag practices like reduced tillage and cover cropping are used to support high levels of SOM for improved nutrient cycling, soil structure, and cation exchange capacity. 

The food webs that produce SOM are characterized by an astonishing diversity of soil life made up of bacteria, fungi, archaea, nematodes, protozoa, and other microfauna, as well as the larger organisms like springtails and earthworms higher up the food chain. These organisms not only drive nutrient cycling through consuming and contributing to SOM, but can influence crop health through more specialized relationships. Plant-growth promoting rhizobacteria that interact with plant roots can boost crop productivity by producing hormones, fixing atmospheric N, solubilizing P for increased availability, and inducing plant resistance to pathogens. The growing biologicals industry (biopesticides, biofertilizers, and biostimulants) is based on the premise that certain organisms benefit crop health through either direct interactions or interactions with other soil life. 

Keeping in mind how soil biodiversity and activity affect soil health through the lens of SOM and interactions between organisms can help us make decisions that support crops by maintaining a thriving, balanced soil habitat.

Examples of soil organisms at different scales – Microfauna: Azospirillium soil bacteria (top), Mesofauna: tardigrade (middle), Macrofauna: earthworm (bottom). Photos courtesy of Science Source (top), National Geographic (middle), Dan Brekke – Flickr (bottom).

Crop Updates



Plectosporium leaf blight is being detected. Continue to watch for aphids, cucumber beetles and squash bugs. Significant damage was detected within the last week in harvested pumpkins due to large populations of cucumber beetles. Aphids can still be found in green foliage, and may be spotted via large accumulations of honey dew beneath healthy foliage.

Cucumber beetles feeding on harvested pumpkins. Photo by Frank Becker, OSU Extension.

Cole Crops

Alternaria leaf spot is being observed in brassicas. This pathogen is supported by warm, wet conditions. Cultural practices for reducing alternaria pressure include increasing crop spacing for improved airflow, crop rotation, tilling under crop residue after harvest and controlling brassica weeds (shepherd’s purse, wild mustard, wild radish, yellow rocket, etc.)  to decrease disease inoculum. Treating seed with hot water prior to planting may also help  to decrease prevalence of this seed-borne pathogen. Consult the Midwest Vegetable Guide for fungicide options in Brassicas.


Hoop house tomatoes are nearing the end. Powdery mildew, bacterial diseases, aphids, and other pests are all being observed under plastic. Late blight and early blight are prevalent in remaining field tomatoes. 

Anthracnose is continuing to be an issue on peppers and tomatoes. Infested fruits rapidly decline in quality and are unmarketable. Lesions are typically observed as sunken, round lesions on the fruit. At times you may also be able to see the salmon colored spores within the lesion on the fruit. 

Anthracnose on peppers. Photo by Frank Becker, OSU Extension. 


Many orchards are nearing completion of harvest and pest monitoring traps are being taken down for the season. As tree fruits are harvested and leaves begin to fall, it may be a good opportunity to take a closer look at your trees and scout the trunk and branches for presence or evidence of insect pests such as scale and borers. Scouting for these pests now can help you make adjustments to your integrated pest management program.

October Small Fruit Updates

Dr. Gary Gao, Professor and Small Fruit Specialist, CFAES South Centers. The Ohio State University

Update on Long Cane Raspberry Project:

We are only getting a few straggling raspberries from our long cane raspberry trial at OSU South Centers in Piketon during the week of October 6, 2023. There were only enough for Gary to snack on. Pictured in the first photo is Kweli®. As you can tell from the picture, fruit color is still looking quite nice. Kweli® is an everbearing variety that is capable of producing two crops inside a high tunnel and out in the open field. Follow this link for more information on the variety: https://www.abbreeding.nl/varieties/kweli/?lang=en

We are still fine-tuning the method of growing long cane Kweli®. We just wrapped up our 2021-2023 Specialty Crop Block Grant (SCBG) funded by Ohio Department of Agriculture (ODA). There is a lot more to learn about this highly innovative production method. Fortunately, we received another SCBG from ODA to do just that!

Kweli® fruits. Photo by Dr. Gary Gao, The Ohio State University.

Gary was able to find several Tulameen raspberries from our long cane raspberry trial plot. This is definitely too late for the Tulameen harvest since it is a summer-bearing variety which does not produce fruits on primocanes. It was still neat to check them out. Earlier in the season, we harvested a lot of beautiful Tulameen fruits. Some of our grower cooperators were able to sell them for $9 per pint in a Columbus farmer’s market. Raspberry bushes in a long cane production system can produce 22,000 lbs. per acre! Tulameen is well suited for long cane raspberry production and is well known for its large fruit size and excellent taste! Follow this link – https://www.researchgate.net/publication/292928034_’Tulameen’_red_raspberry – for more information on Tulameen variety.

Tulameen fruits picked in October from our long cane raspberry trial. Photo by Dr. Gary Gao, The Ohio State University.

Late Leaf Rust on Raspberries:

Gary noticed that some of the raspberry bushes in their raspberry trial had late leaf rust. Late leaf rust on raspberry is a fungal disease. Follow link – https://ohioline.osu.edu/factsheet/plpath-fru-17#:~:text=Late%20leaf%20rust%20is%20caused,rust%20fungus%20is%20not%20systemic. -for more information on symptoms and management of this disease. Do not confuse this disease with orange rust of brambles. Fortunately, red raspberries are resistant to orange rust.

Late leaf rust on raspberries. Photo by Dr. Gary Gao, The Ohio State University.

Fall is for Figs in Ohio!

Even though fall is typically for apples, mums, and pumpkins, it is also for figs – well hardy figs for that matter. Gary has been picking hardy figs from their fig planting at OSU South Centers in Piketon from early September to now. The figs will keep ripening until frost. A high tunnel will extend the harvest season.  Our figs were from another Ohio Specialty Crop Block Grant funded by ODA a few years ago. The varieties in our trial are Brown Turkey, Hardy Chicago, and Olympian. Brown Turkey and Chicago Hardy performed the best in our trial. Follow this link https://ohioline.osu.edu/factsheet/hyg-1439 for more information.

OSU hardy fig trial. Photo by Dr. Gary Gao, The Ohio State University.

Brown Turkey figs from the hardy fig trial at OSU South Centers in Piketon. Photo by Dr. Gary Gao, The Ohio State University.

Berry Production Workshops Presented by OSU Extension in Medina County

I will be going to Medina County on Friday, October 27 to give two talks, one on blueberries and one on raspberries. Ms. Ashley Kulhanek, the Ag. and Natural Resource Educator, is organizing the program. I will show gardeners and growers how to grow blueberries and raspberries. Please call OSU Extension in Medina County at 330-725-4911 for more information and to RSVP!

This is our last bi-weekly report for the 2023 season. Thank you for reading and please feel free to direct any feedback on the report series to Chris Galbraith at galbraith.108@osu.edu.

Upcoming Events

December 5 – 7, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo 

January 15 – 16, Columbus, OH, 2024 Ohio Produce Network

February 15 – 17, Newark, OH, 2024 Ohio Ecological Food and Farm Association (OEFFA) Conference


OSU Extension Bi-Weekly Fruit & Vegetable Report – September 28th, 2023

The OSU Extension Fruit & Vegetable Report is written/published collectively by OSU Extension staff across the state. 

View a recording of the OSU Extension Bi-Weekly Fruit & Vegetable Report updates below:

Strip Tillage

Strip tillage is a form of conservation tillage that attempts to combine the benefits of no-till and conventional tillage by working only the area where the crop will be planted. Leaving residue cover over the majority of the field protects the soil against erosion and helps to build organic matter, improve aggregate stability, and boost other indicators of soil health. Working the soil in the strip zone warms the soil faster and prepares a better seedbed to support plant growth. 

Components of a strip till unit – A) lead coulter for slicing through residue, B) row cleaners for parting residue, C) shank for fracturing and lifting soil, D) berm-building coulters to shape tilled soil into strip, & E) rolling basket for creating level seedbed. Photo courtesy of Orthsman/Unverferth Manufacturing. 


Strip-till in sweet corn stubble. Photo by Chris Galbraith, OSU Extension.

While strip till targets the benefits that come with integrating the two systems, there are downsides to consider as well. These mostly involve issues with cover crop and/or residue interference with growing the crop. Vigorous cover crops need to be terminated in a timely fashion and crop development can still be delayed in strip-till if the season begins cold and wet. Pests like slugs and voles can also build-up with the increased residue cover. The cost of the equipment can also be a substantial investment which creates a barrier to entry for many growers.

Many vegetables can be grown in strip tillage systems, including cucurbits, sweet corn, snap beans, potatoes, cole crops, carrots, and more. Recent studies at Michigan State University have found a slight yield increase from strip till in vegetable crops, but many of the issues mentioned can impact this (climate, residue management, pest pressure). It is important to consider the factors that go into making strip till a successful venture in order to make the most of the equipment and the practice.

For additional info on strip till in vegetables, check out this website on strip tillage from the Cornell Small Farms Program. 

Wildlife Control in Fruits & Vegetables

This season has been severe in terms of wildlife damage in specialty crops. Animals like deer, groundhogs, voles, raccoons, and birds have caused major losses on some farms. Dr. Marne Titchnell, wildlife program director for OSU Extension, recently gave an in-depth presentation at Farm Science Review on different wildlife mitigation strategies for growers. The information and slides can be found on her blog through the link below:

Managing and Preventing Damage from Wildlife in Fruits & Vegetables

OSU Extension Center for Cooperatives

Opportunities abound for farms when it comes to teaming up to save money and improve effectiveness through joint purchasing, collaborative marketing, and other similar practices. These types of partnerships between farm businesses is captured by the cooperative or “co-op” model where growers access resources and savings by acting together and making decisions as a group in certain scenarios. The Center for Cooperatives at OSU specializes in these sorts of opportunities and can offer guidance to growers who are interested in leveraging the benefits of organizing for collaborative business purposes.

Find more information at the center’s website. Read more about the topic of collaborative marketing in this recent article on the Center of Cooperatives blog.

Crop updates


Cole Crops

Heavy cross striped cabbageworm and imported cabbageworm feeding is still being observed in some brassica plantings. Aphids have made a late season push in brussel sprouts, cabbage, cauliflower and broccoli plantings. Cabbage aphids are typically a grayish color, and are often found amongst a waxy, white secretion which covers their body. Reproduction rates of these aphids are highest in temperatures between 50-68F. Scout for these pests on the underside of younger leaves, between leaf layers and on flower buds or seed stalks. It is recommended to treat cabbage when you see 1-2% of plants infested with aphids. There are a number of products that can be used to treat aphids in cabbage including Movento, Sivanto, Assail, Exirel and Beleaf. Prioritize products that have reduced toxicity (e.g., Beleaf) which will conserve natural enemy communities. Refer to the Midwest Vegetable production guide for other options. 

Cabbage aphid infestation. Photo by Frank Becker, OSU Extension. 


Cucurbits are seeing upticks in a variety of beetles in flowers and fruit. These include corn rootworm species. Spotted cucumber beetles are active. Aphids are also beginning to be found with some more frequency in the fall vine crops. Squash bugs are also active within the crop. Most cucurbits do not have blooms in fields, so pyrethroid and carbamate applications may be applied (e.g., Sevin, Pounce, Capture). Refer to the Midwest Vegetable production guide for other options.

The pumpkin crop has been strong in Ohio this season. Many growers in northwest Ohio were able to manage downy mildew with fungicides. Plectosporium blight has been causing some problems for growers where fungicide spray coverage may not have been as thorough as desired. Most fungicide spray programs being used are adequate to limit impacts from plectosporium blight. Spray penetration into the canopy and coverage across the field is as important as selecting the right product.

Plectosporium blight on pumpkin, identified by light colored lesions on fruit, handles, and vines.  Photos by Frank Becker, OSU Extension.

Fruiting Vegetables 

Late blight has been confirmed in several tomato fields in and around Wayne County. Bacterial diseases have also begun to start, and with cool mornings and heavy dews, it will become increasingly more difficult to manage. 

Several high tunnel producers have reported dealing with broad mites/cyclamen mites in their high tunnel peppers. The mites feed on the fruit while it is still developing and their feeding damage causes the peppers to become russested and misshapen. The leaves may also appear distorted, almost as if they were drifted with herbicides. Keep in mind that these mites are in a different group than two-spotted spider mites. Therefore, it’s important to select control options that are appropriate and effective on this species. Sanitation and crop rotation are also important cultural control measures that need to be taken when dealing with mites in high tunnels.  


Although the growing season is behind us for onions, curing is still ongoing, and some growers have reported some challenges with curing. Make sure that you are providing the proper conditions for curing onions. Less than ideal conditions will result in frustrations and losses of product. Ideal conditions are warm, dry, well ventilated areas. Ideal temperature range is between 75-90F. The other factor that contributes to losses while curing is not curing the best graded onions. Curing is not an attempt to bring quality back, only preserve it. Grading hard for only the best onions to be cured will help reduce the chance that rots begin to develop. Take note of any disease or insect issues that you have observed this year and use these notes to help you next year. Onions that may have had heavy thrips loads, or untreated disease infection during the season are not going to hold up as well as desired during the curing process. 

Green onions are seeing thrips populations slow down. Typically, thrips populations will decrease as we enter into Autumn and see these species move onto weedy hosts. 


Sanitation is an important component of an integrated disease management program. In small fruit and tree fruit alike, there are diseases that can over winter on infested fruit, foliage and branches. As the season winds down, it is still important to scout for diseases that may be present, identify the disease and have a plan of action to manage the disease. Finding and removing mummy fruit, which are dried and shriveled fruit that are typically full of fungal structures, will help to significantly reduce disease inoculum from the production area. Too, mowing and mulching or raking away the leaves from around the trees and bushes reduces the amount of viable inoculum that may be overwintering in foliage. Much progress can be made towards disease management with efforts made in the fall. Taking these steps, and committing to them long term, helps to break disease cycles and reduce the overall pathogen load over time. 

Fruit rots are being observed in apples, including white rot and bitter rot. Bitter rot is common in apples during warm, wet conditions. For more information, take a look at this OSU article on bitter rot in apple. Marsoninna blotch is also found on apples. 

The pawpaw crop in Ohio this season has been later and smaller than past years. Pawpaw is a niche crop that is gaining popularity with Ohio consumers and can be used as an ingredient in specialty craft beers, ice cream, and other value-added items. For more information on pawpaw production, check out this factsheet from Cornell University. Learn more about the pawpaw industry in Ohio by visiting the Ohio PawPaw Growers Association website.

Pawpaw fruit cluster. Photo by Clemson University. 


Upcoming Events

September 30, Albany, OH OEFFA CSA Veggie Farm Tour

December 5 – 7, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo 

January 15 – 16, Columbus, OH, 2024 Ohio Produce Network

February 15 – 17, Newark, OH, 2024 Ohio Ecological Food and Farm Association (OEFFA) Conference


OSU Extension Bi-Weekly Fruit & Vegetable Report – September 15th, 2023

The OSU Extension Fruit & Vegetable Report is written/published collectively by OSU Extension staff across the state. 

View a recording of the OSU Extension Bi-Weekly Fruit & Vegetable Report updates below:

Farm Science Review 2023

The Farm Science Review (FSR) is one of the nation’s premier farm shows and one of OSU Extension’s largest, most far-reaching educational programs. The event will be held at the Molly Caren Agricultural Center near London, Ohio on September 19th – 21st. The OSU Extension Fruit & Vegetable Team will be hosting a tent all 3 days that will feature presentations from academic and industry speakers on a variety of topics, including nutrient management, entomophagy, integrated pest management, variety trial results, farm marketing, and more. The OSU Extension Fruits & Vegetables exhibit will be located near the gazebo near the Utzinger Garden (booth 385). We hope to see you there!

Check out the 2023 Farm Science Review Program for further information.

Speaker schedule for OSU Extension Fruits & Vegetables exhibit at FSR 2023. Note: There will also be a presentation by Dr. Marne Titchnell, Extension Wildlife Program Director for OSU,  on wildlife management in fruits & vegetables on Wednesday, September 20th from 1:30 – 2:00 PM.

Purple carrot-seed moth detection

The OSU Plant & Pest Diagnostic Clinic (PPDC) recently received an insect sample that was identified to be purple carrot-seed moth (Depressaria depressana), a known pest of crops in the Apiaceae family. This was the first report of purple carrot-seed moth found in Ohio, though it has been found in neighboring states. The insect feeds on the flower heads of crops like carrot, parsnip, dill, celery, parsley, and more, but it is yet unknown if it will be an economically important pest of these crops in Ohio. Check out the article from PPDC for more information.

Please report any suspected larvae/adults with pictures to entomology@osu.edu or ppdc@osu.edu.

Purple carrot seed moth larvae (top) and adult (bottom). Photo by Iowa State University Extension (top) and University of Wisconsin-Madison Department of Entomology (bottom). 

Crop updates



Downy mildew continues to wreak havoc in cucurbit plantings this time of year. As a refresher, here is a factsheet from Michigan State University on downy mildew mitigation. Powdery mildew pressure is reported to be increasing in southern Ohio. Striped cucumber beetles populations are declining in central/northeast Ohio and transitioning more towards higher numbers of corn rootworm beetles. Western corn rootworm, a look-alike of striped cucumber beetle, also feeds on cucurbits and can impact yield if heavy populations are present. Check out this article from Iowa State University for information on identifying different rootworm beetle pests. 

Virus symptoms are being observed in some melon plantings. There are various aphid-vectored potyviruses that affect cucurbits and they can be hard to differentiate from one another, though control practices are similar for all of them. The big 4 for cucurbit crops are cucumber mosaic virus, papaya ring spot virus, watermelon mosaic virus, and zucchini yellow mosaic virus. Like many crop diseases, management practices are preventative and include using resistant varieties or planting earlier to ensure harvest before viral symptoms appear towards the end of the season. Getting aphids under control may also minimize virus infection to some degree.

Cucumber mosaic virus – symptoms include yellowish-green “mosaic” mottling on foliage or fruit and crinkled leaves. Photo by Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, Bugwood.org.

Papaya ringspot virus – symptoms include wrinkled leaves and discolored, bumpy fruit. Photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org.


Watermelon mosaic virus – symptoms include wrinkled leaves and geometric patterns on fruit.  Photo by Dorina Pitorac, European Plant Protection Organization.

Zucchini yellow mosaic virus – symptoms include blistered, wrinkled leaves and fruit with discolored bumps. Photo by University of Massachusetts Extension.

Fruiting Vegetables

Late-season aphid feeding is being observed in some solanaceous crops. Honeydew is a sugary liquid secreted by aphids and other sap-sucking insects (whiteflies, spotted lanternfly, etc.). Honeydew accumulation on crop foliage or fruit can lead to growth of sooty mold, which is a term for various genera of fungi that colonize the sticky exudate. Sooty mold does not render vegetables inedible, however, and can be readily washed off. 

Honeydew from aphids (and other sap-suckers) on plant leaves is sticky to the touch and can be colonized by sooty mold. Photos by Kansas State University Entomology (top) and Joe Boggs, the Ohio State University Extension (bottom). 

Regular bouts of rainfall as we head into the fall are leading to increased incidence of Phytophthora infection in peppers (and cucurbits). While excess water is a problem for some vegetable growers in Ohio, some parts of western Ohio still remain abnormally dry, according to the U.S. Drought Monitor. Mites have been a problem in some areas, while thrips have taken a downturn. Keeping mites under control towards the end of the season can reduce the chance of heavy pressure next season by reducing the egg load/number of overwintering adults that will become next year’s mite infestations.


Tree fruits

Early varieties of apples are being harvested across the state. Brown marmorated stinkbug pressure is increasing. Bitter rot is starting to be observed in some orchards. Marssonina leaf blotch is also being seen in some organic orchards, where management can be difficult without the use of fungicides. Removal/destruction of leaves on the orchard floor in the fall can reduce overwintering sites for the pathogen. Black knot is being seen on some ornamental plum trees, so commercial plum and cherry growers should keep an eye out for black knot galls on their trees and promptly remove them if they see them.

Gall of black knot (Apiosporina morbosa), a fungal pathogen of plum, cherry, and other types of fruit trees. Photo by Joseph O Brien, USDA Forest Service, Bugwood.org.

Small Fruits

Preparing Brambles for Winter – Sanitation Practices for Disease Prevention
Melanie Ivey, State Fruit Pathologist and Fresh Produce Safety Specialist, The Ohio State University

Disease management of perennial fruit crops is a year-round endeavor. Many fungal pathogens survive the winter months in the soil or plant debris, infected canes or buds, or dead canes. As part of an integrated disease management program fall sanitation practices to reduce inoculum in the planting should be done.  Best sanitation practices include removing floricanes after harvest, removing diseased and dead canes, removing dead or systemically infected plants, and raking or chopping fallen leaves. Pruning debris should be destroyed by burning or placing in the trash or discarding it away from the planting. Diseased plant material should not be composted.  Pruning cuts should be sharp and clean to avoid unnecessary mechanical wounds.

The fall is also a good time to scout for and remove wild bramble populations that are near the production field. In addition to fall sanitation practices, some diseases require a dormant or delayed dormant fungicide application. For dormant or delayed dormant fungicide recommendations consult the Midwest Fruit Pest Management Guide (OSU Extension Bulletin 506).

The table below summarizes where the fungi for several common diseases of brambles in Ohio overwinter, the recommended fall sanitation practices for each disease, and whether a dormant or delayed dormant fungicide application is recommended.

Upcoming Events: 

September 19 – 21, Farm Science Review

September 27, Wooster, OH, Midwest Mechanical Weed Control Field Day

September 30, Albany, OH OEFFA CSA Veggie Farm Tour

December 5th – 7th, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo 

January 15 – 16, Columbus, OH, 2024 Ohio Produce Network

February 15 – 17, Newark, OH, 2024 Ohio Ecological Food and Farm Association (OEFFA) Conference

Spotted Wing Drosophila Spotted

Spotted-wing Drosophila (SWD) is one of the major pests of cane berries, blueberries, black berries, strawberries and peaches. Last week it was detected in Greene, Monroe, Geauga and Wayne counties but likely is present and active in most Ohio counties at this point in the season (https://u.osu.edu/jasinski.4/pestvisualization/#linki).

Spotted wing Drosophila male (L) and female (R).

Recall that this pest is relatively new to Ohio, first discovered in 2011, and has the distinction from other drosophila flies of being able to attack whole, healthy fruit as they begin to blush and ripen.

The best way to monitor for this pest on your farm is to use a trap with either a commercial lure or apple cider vinegar as a bait.

Spotted wing drosophila baited Scentry trap.

If you do this, it will be necessary to empty the trap weekly and look through the catch to identify the male (with the spot on its wing) or female (which has an enlarged serrated ovipositor) using a stereoscope. Remember that the threshold for this pest is 1 SWD fly, male or female. Once the threshold is exceeded, trapping can be halted. This can be a fairly intensive endeavor but has been described in detail in various videos posted to the OSU IPM YouTube channel (setting up trap, identification, salt water tests, etc.). https://www.youtube.com/playlist?list=PL0HRPaZDLHyFqKGmNic832l0SWqMO8IQ4

If you choose not to monitor for this pest and have had SWD on your farm before, it is nearly 100% certain they will return once fruit is in the blush or ripe stage, so you should prepare to manage based on their assumed presence. A fact sheet on SWD giving more detail on management and biology with an up to date list of insecticides can be found here: https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/1/8311/files/2020/11/SWD_Ohio_handout_V20.pdf

Once you decide to stop harvesting in a certain block, insecticide treatment for SWD can be halted. For smaller or organic growers, some cultural methods including use of black mulch, pruning and netting have been shown to reduce and delay infestation.

Medina County grower talking about his exclusion netting project to manage SWD.

Spotted-wing Drosophila still active on small fruit

Although we are moving toward the end of the season for most small fruit producers, keep in mind that spotted-wing Drosophila populations remain high across the state where traps have been placed on farms. Because of their short life cycle and abundance of ripe fruit, expect these populations to increase up until the first significant frost/freeze event.

SWD larvae in fruit

For growers who have abandoned their small fruit plantings for this year, SWD adults can easily be seen buzzing around ripe fruit as they oviposit eggs beneath the soft skin. Evidence of infestation can be readily seen as soft juicy fruit are filled with white SWD larvae. Even for growers who have maintained a regular spray schedule to control this insect, SWD adults can still be detected flying around bramble and blueberry patches albeit in lower numbers.

Since the threshold for this pest is only one adult per trap, it is necessary to maintain a spray schedule as long as the farm intends to harvest fruit. Once the decision has been made to end harvest, the sprays can be halted.

Stink Bugs on My Mind…and Camera

Overwintering BMSB getting active inside house.

While sitting at my home office desk this rainy afternoon, an annoying BMSB adult started buzzing around my head, landed on the window and then flew to the door, a subtle reminder to write this brief article. Earlier this week I was able to get out and shoot a quick video about identifying, monitoring and managing Brown Marmorated Stink Bug (BMSB). If you are interested to learn the current details of how to trap for this pest, take a look at the final video on the OSU IPM YouTube channel (https://youtu.be/PVtY-c92ZdM).

Distribution of BMSB based on trapping network in 2019.

While BMSB has an appetite for most fruit and vegetable crops plus corn, soybean and other hosts, it generally has not developed into a significant pest in Ohio as in states further east and into the mid-Atlantic region.  Our efforts to monitor this pest over the years has evolved with new trap designs and aggregation lures. The results of our monitoring seem to suggest the pest is slowly increasingly in the central, southwest and eastern areas of the state.

Sticky panel trap with pheromone lure.

While BMSB is beginning to become active now, most of the damage can be expected in the summer months on green and ripe fruit. In August and September, BMSB becomes more mobile and is attracted to sticky panel traps baited with pheromone lures. Unfortunately, the only crop with a threshold using the sticky panel traps is apples. For each apple block (ca. 5A) place one baited sticky trap at the edge and one in the interior about 50m away; when either trap catches 4 or more BMSB adults or nymphs, a treatment may be justified. Since BMSB tends to be an edge pest, a perimeter spray may be an effective way to treat this pest instead of the entire orchard.

For other crops, place a trap at the field edge, interior of the field or near a wooded border that is adjacent to a crop field to get an early determination if BMSB is in the area. One of the goals of current BMSB research is to develop more thresholds for other crops to help guide management decisions. Until then growers will have to resort to frequent scouting for nymphs an adults of BMSB and several other pest stink bugs in their crops.

Dr. Celeste Welty has much more information related to identification, biocontrol, damage and treatment of BMSB on her website (https://u.osu.edu/pestmanagement/pests/bmsb/). Additional information can be found at https://www.stopbmsb.org.

Be on lookout for thrips on strawberries

Thrips can be a serious pest of strawberries, but they are an occasional pest. This means that in most years, they are not a problem, but in some years, they can be a big problem. The reason for variability from year to year seems to be related to weather systems. In some years, conditions are right that large numbers of small insects such as thrips and leafhoppers blow into Ohio on weather fronts from the southern USA during the time that strawberries are in bloom. In other years, this long-distance movement does not happen at all, or happens later, at a time when strawberries are no longer in bloom. Due to the irregularity in the occurrence of thrips, it is a pest that is well suited to weekly scouting, for early detection of any infestation.

Strawberry fruit that have been injured by thrips are a dull or bronzed color, and are often small, hard, seedy, and fail to ripen (Figure 1). Thrips can cause uneven maturity of fruit. When thrips are abundant and the berry injury is severe, the result can be a strawberry crop that is completely unmarketable. Diagnosis of thrips injury can be tricky because thrips are not the only cause of fruit bronzing. Bronzing can be due to feeding by cyclamen mite or two-spotted spider mite, or to infection by powdery mildew, or to occurrence of low temperatures or hot dry winds, or to pesticide spray effects.

Thrips are often overlooked due to their small size and their tendency to hide in protected places. Thrips are weak fliers but fast runners. Thrips are small, slender, elongate, ‘cigar-shaped’ insects (Figure 2), about 1 mm (1/25 inch) long as adults. They differ from other insects by having narrow strap-like wings that are fringed with hairs. The wings are usually folded lengthwise over their back when they are resting or feeding. The immature thrips are the same shape as adults but smaller and without wings. Thrips have lopsided mouthparts that have a well-developed left mandible and an underdeveloped right mandible. They feed by piercing and scraping plant cells with the mandible then sucking sap that oozes out of the punctured cells.

The thrips species that most commonly infests outdoor strawberries is Frankliniella tritici, which has the official common name of ‘flower thrips’, but which is widely known as the ‘eastern flower thrips’. The adults are yellowish brown, and the immatures are whitish-yellow. The eastern flower thrips does not tolerate cold weather, so does not survive winter well in places like Ohio. The eastern flower thrips has a wide host range that includes many flowering weeds, where the thrips population can build up before moving into a cultivated crop like strawberries.

The eastern flower thrips looks quite similar to three other species of thrips that inhabit Ohio and have been reported from strawberries: the western flower thrips (Frankliniella occidentalis), the tobacco thrips (Frankliniella fusca), and the onion thrips (Thrips tabaci). The western flower thrips is the species commonly found in greenhouses; it is generally much more difficult to control than other thrips because it is usually resistant to most insecticides. In greenhouses, the western flower thrips causes injury to tomatoes, peppers, and cucumbers as well as to strawberries. The onion thrips is best known as a serious pest of dry bulb onions, green onions, and cabbage but is sometimes found on other crops.

Thrips generally prefer to feed on flowers rather than other plant parts, but they can feed on leaves and fruits. On strawberries, the infestation starts by adult thrips being attracted to flowers, and the female inserts eggs at the base of flowers. Each female can lay about 80 eggs. Infestation can continue during fruit set by adults and their immature offspring. Thrips feed on pollen, seeds, and the fruit tissue between seeds. Thrips hide under the cap of the berry or in grooves around the seeds on the berry.

A key to thrips management is frequent monitoring by scouting, at least once per week. Growers should designate one person on the farm to be sure that scouting is done every week. Where multiple varieties are present, each variety should be scouted separately. The scout should begin the season by examining early flower clusters on early cultivars, as soon as the first blossoms open. Scouting should be done in five different areas within small fields or in ten different areas within large fields. In each area, 10 blossoms should be tapped into a white cup, or into a zip-top sandwich bag, which should then be examined for the dislodged thrips running around on the surface. Count the number of thrips found, then calculate the average number of thrips per blossom. The action threshold for treatment with insecticide, used the midwestern USA, is the presence of 2 or more thrips per blossom. This is a conservative threshold that is lower than a threshold of 10 thrips per blossom that is used in some mid-Atlantic and California regions.

Scouting should continue after fruit set, until fruit are ½ inch diameter, by examining 50 fruit in each area, and counting thrips on those fruit. Fruit can be examined in place, or removed and put in a plastic zip-top bag, which can be placed in a sunny location so that the heat forces the thrips to leave their hiding spots and begin running around on the bag surface. Once fruit are ¼ inch in diameter, an action threshold is 0.5 thrips per fruit.

If thrips are above threshold, the trickiest part of management is to avoid spraying insecticide that will harm pollinators. Insecticide should not be applied during bloom, to protect bees and other pollinators. Insecticide should be applied pre-bloom or before 10% of the plants have open blossoms. If thrips are found above threshold on early cultivars, then a preventive spray can be made on the later cultivars before their flowers open, to avoid harming pollinators. If insecticide is needed during bloom, it should be applied in the evening when bees are least active. Sprays targeted at tarnished plant bug or spittlebug or strawberry clipper weevil, just before bloom, often do a good job of controlling any thrips that also are present.

Insecticides used to manage thrips on conventional strawberries include several products that are labelled for control, and several that are labelled only for suppression (Table 1). Products for control of adult and immature thrips are Radiant, Assail, Apta, and Dibrom, all of which have thrips listed as a target pest on their labels. Note that use of Apta on strawberries appears on a supplemental label, not the federal label. A product for control of immature thrips, but not adults, is Rimon. Products for suppression of thrips are Closer, Exirel, Sivanto, Transform, and Verdepryn. In addition, there are several products that are allowed for use on strawberries, but that do not list thrips as a target pest on strawberry, however thrips are a target pest of these products on other crops; these are Admire Pro, Agri-Mek, Brigade, Danitol, Harvanta, Lorsban, and Malathion. Note that Lorsban has a 21-day pre-harvest interval thus is for use only pre-bloom. Beware that pyrethroid insecticides such as Brigade and Danitol are no longer as effective as they were in the past due to the development of resistance in thrips populations at many locations. An adjuvant that can be helpful in control of thrips is Wetcit, which is a penetrant, spreader, and wetting aid.

Products for thrips control on organic strawberries are Entrust, azadirachtin products such as Neemix and Aza-Direct, and the beneficial fungus Beauveria bassiana, as well as other natural products (Table 2).

An important natural enemy of thrips is the Orius predatory flower bug, which is a very small true bug that preys on thrips adults and thrips larvae. Orius insidiosus is a common species in Ohio on many crops; it is frequently found on the moist fresh silks of sweet corn and on flowers of Queen Anne’s lace. There are also several species of predatory mites that prey on thrips. The local population of these natural enemies is often inadequate to suppress thrips, but growers who would like to take a biological control approach to thrips management can purchase natural enemies from commercial insectaries: Orius (predatory flower bugs), and four species of predatory mites: Ambylseius swirskii, Neoseiulus (Amblyseius) cucumeris, Amblydromalus limonicus, and Stratiolaelaps scimitus (formerly Hypoaspis miles). Beneficial nematodes such as Steinernema feltiae are another option. Some suppliers of these natural enemies are IPM Labs, Koppert, BioBest, and Rincon-Vitova. Biocontrol is not feasible to begin once the thrips population is large, but can be planned in advance at locations that have a consistent problem with thrips.

-Celeste Welty, Extension Entomologist


Beware of thrips!

The current hot, dry weather can be conducive to outbreaks of thrips. Thrips are very small, slender, elongate, cigar-shaped insects, about 1 mm (1/25 inch) long. They differ from other insects by having thin strap-like wings that are fringed with hairs. The wings are usually folded lengthwise over the back when they are resting or feeding, as shown in the image below. They have asymmetrical mouthparts that have a well-developed left mandible and an underdeveloped right mandible. They feed by piercing plant cells by the mandible then sucking sap that oozes out of the punctured cells.

Smaller, tan thrips on left is the onion thrips (Thrips tabaci). Larger yellowish thrips on the right is the western flower thrips (Frankliniella occidentalis).
Photo by Alton N. Sparks, Jr., University of Georgia, Bugwood.org

Thrips generally have flowers as their preferred plant part but they also feed on leaves and fruits. They are found in flowers of many ornamental plants but also on various vegetables and fruit crops, including tomatoes, peppers, and cucumbers. Thrips are often overlooked due to their small size and their tendency to hide in protected places. When present at low density, thrips are usually not harmful to crops, but when they reach higher density, they can feed on the surface of fruits and cause injury.

The thrips species that infests many outdoor crops is Frankliniella tritici, which has the official common name of ‘flower thrips’, but which is widely known as the eastern flower thrips. The thrips species that is most common in greenhouses is the western flower thrips, Frankliniella occidentalis, which is generally much more difficult to control than other thrips because it is not highly susceptible to most insecticides. A third common species is the onion thrips (Thrips tabaci), which is a serious pest of dry bulb onions and green onions as well as cabbage.

Natural enemies of thrips are Orius flower bugs, which are very small predatory true bugs that prey on thrips as adults and nymphs. Orius insidiosus is a common species in Ohio that is frequently found on the moist fresh silks of sweet corn and on flowers of Queen Anne’s lace. There are also several species of predatory mites that prey on thrips.

Insidious flower bug (Orius insidiosus) feeding on an insect egg.
Photo by John Ruberson, Kansas State University, Bugwood.org


Orius bug feeding on a thrips.
Photo by Robert Webster / xpda.com / CC-BY-SA-4.0 via Wikimedia Commons.

Thrips can be monitored by shaking flowers over a paper or into a cup or zip-top sandwich bag, which should then be examined for the dislodged thrips running around on the surface. Action thresholds have not been developed for most crops, but on strawberry we use a threshold of 2 thrips per flower.

In the past, pyrethroid insecticides provided control of thrips, but there are widespread observations that pyrethroids are no longer very effective for thrips control at most locations. Newer insecticides used to control thrips on conventional crops include Radiant, Assail, and several others, as shown in Table 1 below. Products for thrips control on organic crops include Entrust and various others as shown in Table 2 below.

If a biological control approach is preferred, natural enemies are available for purchase from commercial insectaries for thrips control: Orius (predatory flower bugs), and two species of predatory mites: Amblyseius cucumeris and Ambylseius swirskii. Beneficial nematodes such as Steinernema feltiae are another option. Microbial options include sprays of the beneficial fungus Beauveria bassiana, which is found in several commercial products. Biocontrol is not feasible to begin once the thrips population is large but can be planned in advance at locations that have a consistent problem with thrips.

-Celeste Welty, Extension Entomologist

Insect observations

A few Japanese beetles were sighted today on a peach tree in Columbus. Late June is the usual time that this pest begins to emerge. Beware that large congregations might be seen on their preferred crops over the next few weeks. Japanese beetle is a pest of sweet corn, snap beans, raspberries, grapes, plum, peaches, blueberries, and hops as well as ornamental plants such as roses and linden trees and sassafras, and weeds such as smartweed. This pest can be more readily controlled by insecticides if the spray is made when the congregations are just beginning to form. Insecticides that are very effective for control of Japanese beetle are old ones: carbaryl (Sevin) and pyrethrins plus PBO (EverGreen Pro).

True armyworm is active in corn fields and grassy areas. We previously reported a large surge in the number of armyworm moths caught in our blacklight trap in Columbus between 5/14 and 5/18, with a record of 210 moths in one night on 5/14. We have been seeing increased numbers of moths during the past week, including today when there were 96 armyworm moths in the trap. There have been reports of armyworm larvae being found in field corn fields around Ohio. Daily counts of armyworm and several other common moths in blacklight traps are posted here:  https://docs.google.com/spreadsheets/d/10gh3rHahdxLKkXQapGyEPxWsjHYRmgsezOoFHnwtyEo/edit#gid=1114468121

Squash vine borer is now active, and abundant at our research farm in Columbus. Its adult is a day-flying moth that will be laying eggs on zucchini and other summer squash, winter squash (except butternut), pumpkins, and gourds over the next few weeks. It generally is a severe problem in home gardens and in small plantings, but less severe in large fields. Insecticide can be effective if directed to the base of the main stem before eggs have hatched, usually at least 2 or 3 sprays at 10-day intervals. Insecticides used for its control are pyrethroids such as Asana (esfenvalerate), Pounce (permethrin), Warrior (lambda-cyhalothrin), MustangMaxx (zeta-cypermethrin), or Brigade (bifenthrin); it is usually not well controlled by Sevin (carbaryl). We have found that EverGreen Pro (pyrethrins plus PBO) is effective although squash vine borer is not listed as a target pest on its label. This year we have a field trial in progress to evaluate the non-chemical tactic of a border trap crop of unharvested zucchini.

Corn earworm has been active for the past few weeks but at low numbers, which is typical of this pest in Ohio in early summer in most years. We have not seen the surge in moth activity like we did last year in late May and early June. A pheromone trap is highly effective at detecting the presence of the moth. Farms with early planted sweet corn should have their trap out as soon as tassels are emerging. Information on using traps is available here: https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/1/8311/files/2014/12/CornTrapInstructions2009-u47rp3.pdf   Information on buying traps to monitor corn earworm is here:  https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/1/8311/files/2019/07/TrapSpecsAndSources2019.pdf . Trap counts from several Ohio locations are posted here: https://docs.google.com/spreadsheets/d/10gh3rHahdxLKkXQapGyEPxWsjHYRmgsezOoFHnwtyEo/edit#gid=0

Potato leafhopper is active and being reported from beans, potatoes, apples, and hops. The adults and nymphs of this pest are found on leaf undersides where they suck sap. Their feeding results in yellowing then browning along the edge of leaves, a symptom known as ‘hopperburn’. Leafhoppers can be controlled by sprays of a neonicotinoid such as Admire (imidacloprid) or Assail (acetamiprid), or a pyrethroid such as Pounce (permethrin), Warrior (lambda-cyhalothrin), MustangMaxx (zeta-cypermethrin), Brigade (bifenthrin), or by dimethoate.

Brown marmorated stink bug is active now. Our traps are catching only adult stink bugs so far, but a few young nymphs have been seen on host plants. This year we are continuing our investigations of the samurai wasp, which is a tiny parasitoid that specializes in killing the eggs of this stink bug. We have a colony of the samurai wasp at OSU, and we have made releases of it at ten Ohio fruit farms, in comparison with 10 Ohio fruit farms where we did not make a release. We are currently sampling those 20 farms to see if the samurai wasp has become established.

Spotted lanternfly: This invasive exotic pest has NOT yet been found in Ohio, but many people are on the lookout for it, especially in eastern Ohio, because it has been spreading from its initial infestation in eastern Pennsylvania. Its favorite host plant is the tree of heaven but it can cause damage to grapes, hops, blueberries, and other fruit crops, mostly in late summer.

-Celeste Welty, Extension Entomologist