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 below:
Spotted Lanternfly
Thomas Becker, Lorain County Extension Educator, OSU Extension
Quarantine map of spotted lanternfly (top) and adult spotted lanternfly (bottom). Images by Ohio Department of Agriculture (top) and Thomas Becker, OSU Extension (bottom).
ANR educators from across the state have been busy over the recent weeks tracking infestations of spotted lanternfly. At this point in the year, we are finding mostly adult spotted lanternfly with a few 4th instar nymphs still lingering. The current primary host plants for spotted lanternfly are tree of heaven and wild grapevine. They have a wide range of hosts, but as Ohio State specialty crop entomologist Dr. Ashley Leach put it, tree of heaven and wild grapevine are “gateway hosts”. While the 4th instar nymphs and adults are quite sizable and more showy, making them a bit easier to spot, they can be detected earlier in the year by locating their egg masses and watching for the 1st-3rd instar nymphs. The egg masses can be particularly difficult to find, as they can camouflage rather well with the surface they are attached to, especially if that surface is the side of a tree. The 1st-3rd instar nymphs are black with white spots. The 1st instars are very small, only about ¼ of an inch. The 2nd and 3rd instars look about the same as the 1st, but they get larger as they progress through their development. The 4th instars are about ½ an inch in length and are mostly red with some black and they maintain their white spots. The adults are about 1 inch in length and about 0.5 inch wide. Their front set of wings is tan with black spots and their hind wings are red and white with black spots. They have their wings folded back most of the time, so your best chance at seeing the red hind wings is when they are in flight. The spotted lanternfly is not a strong flier. They have more of a gliding flight pattern, climbing up to someplace high and then launching themselves to glide to a new location.
Spotted lanternfly egg mass (top), early instar nymph (middle), and 4th instar nymph (bottom). Photos by Thomas Becker, OSU Extension.
The main concern with the presence of spotted lanternfly is their anticipated movement into some of our fruit crops, especially grapes. So far, many infestations are being found in tree of heaven and wild grape vines near railroads. Spotted lanternflies really aren’t a fly at all, they are a planthopper in the order Hemiptera. They have a piercing, sucking mouth part called a proboscis that they use to feed on the sap of their host plants. With high enough pressure from spotted lanternfly, plants can be weakened which can result in a decline in the overall health of the plant and could potentially lead to some dieback issues. They will also excrete honeydew which results in sooty mold. Since they can feed in such large numbers at times, the extent of the sooty mold can be impressive. The honeydew can also attract other unwanted insects that feed on the sugars found in the honeydew.
Group of spotted lanternfly adults. Photo by Thomas Becker, OSU Extension.
We ask that producers and homeowners alike keep an eye out for this pest and report your suspected findings. If you are able, collect the insect in a bag or jar and put it in the freezer or add a paper towel soaked with some rubbing alcohol to the container that you captured it in. If you are unable to capture the insect, try your best to get a clear picture of it for reporting purposes and get a nearby address or GPS coordinates of the site where you found the insect. You can then make a report using the online reporting system on the ODA website: Spotted Lanternfly (SLF) | Ohio Department of Agriculture
If you have questions, you can also reach out to your county extension’s Agriculture and Natural Resource educator. Here are some links with more information on spotted lanternfly:
“Seeing Spots – Spotted Lanternfly and Spring Egg Hatch” – OSU Extension
“Spotted Lanternfly Continues To Spread Across Ohio” – OSU Extension
Spotted Lanternfly Damage | CALS
Crop updates
Vegetables
Brassicas
Rhizoctonia fungi have recently been implicated in transplant loss of cauliflower in Highland county. This soil pathogen infects the surface of stem tissue at or below the soil line causing the appearance of the stem to rot off and the remainder of the plant to wither. This same pathogen is also responsible for damping off in direct-seeded plantings. No curative treatments are available. Preplant fungicide seed treatments and not planting transplants too deep are preventative measures. Wet and warm soil conditions exacerbate the issue.
Wirestem (Rhizoctonia) symptoms in cauliflower transplants – rotting stem tissue below the soil (left) and withering/decline of the plant (right). Photos by Logan Minter, OSU Extension.
Cucurbits
Squash vine borer population numbers have dropped as the single generation nears its end. Damage from caterpillars earlier in the season can still be observed in the form of boring/feeding damage in squash and pumpkin fruit. Squash bug pressure remains high in northern Ohio but has still been manageable with insecticides. Whitefly populations have been increasing recently in cucurbits and solanaceous crops. Leafhoppers may be being moved up into Ohio with recent weather systems and hopper burn is being observed on some crops. Phytophthora is still being observed in some fields, with lesions observed on mature watermelon fruit.
Squash vine borer larvae damage on pumpkin fruit. Photo by Chris Galbraith, OSU Extension.
Fruiting Vegetables
Processing tomato harvest continues in NW Ohio. Copious amounts of foliage in high tunnel tomatoes have been leading to a higher prevalence of leaf diseases.
Brown marmorated stinkbug and harlequin bug trap catches have been picking up. These insects, along with tarnished plant bugs, spotted lanternfly, squash bugs and other similar pests, are of the order Hemiptera and considered “true bugs”. These insects have piercing-sucking mouthparts that leave cosmetic defects on fruit in the form of small, dark feeding wounds surrounded by light, colored blotches. On tomatoes, feeding can also introduce fruit-rot pathogens or cause fruit tissue below the skin to take on a corky texture that reduces quality. For more information and images, check out this article from the Buckeye Yard & Garden Hotline. Migration of brown marmorated stinkbug into Ohio usually peaks around late September, bringing higher populations and risk of feeding.
Thrip and aphids populations have decreased slightly in the last few weeks, while mite numbers have gone up due to some hot, dry days.
Brown marmorated stink bug body and mouthparts. Photos by Patrick R. Marquez, USDA APHIS PPQ, Bugwood.org.
Symptoms of stink bug feeding on tomato fruit. Photo by Joe Boggs, OSU Extension.
Sweet Corn
Corn earworm pressure is up slightly in a few counties in northwest Ohio as a weather system from the south pushed corn earworm populations up into the region. European corn borer, a non-migratory insect, is still showing low trap counts throughout Ohio. Western bean cutworm trap counts have dropped off as the single generation has passed its peak. Keep up to date on statewide sweet corn moth trap counts through the C.O.R.N newsletter put out by the OSU agronomy team. The insect tracker on the insectforecast website can also help you visualize and plan for pest migrations into Ohio.
Fruits
Peach harvest is wrapping up for the season. Grape cane borer has been reported recently. With the loss of Lorsban (chlorpyrifos) in specialty crop production, there are few options for control of the pest. Disposing of pruning brush from vineyards can help to decrease sites that harbor grape cane borer.
On-Farm Research on the use of Entomopathogenic Nematodes as a biological control of Spotted Wing Drosophila
Dr. Gary Gao, Professor and Small Fruit Specialist, CFAES South Centers, The Ohio State University
Steinernema feltiae (SF) is an entomopathogenic nematode (EPN). It has been shown to significantly reduce adult spotted wing drosophila (SWD) emergence at the pupal and infested fruit life stage, as discussed in a poster presentation entitled “CAN NEMATODES AID IN SPOTTED WING DROSOPHILA (DROSOPHILA SUZUKII) CONTROL?” by Emilie Cole, Jacqueline Perkins, Rufus Isaacs, and Marisol Quintanilla. Steinernema feltiae (SF) treated pupae had significantly less adult emergence compared to the control.
As a part of the USDA-NIFA funded project, Dr. Gary Gao and his research assistant Ryan Slaughter conducted an on-farm EPN study at the largest blueberry farm in Lexington, Ohio. We sprayed Steinernema feltiae on the ground beneath the blueberry bushes weekly at the rate of 1 billion per acre on July 14th, 21st and 28th, 2023. Three bushes of the control and treated blocks were netted with insect netting to prevent cross contamination from neighboring plots. There were three replications. The number of SWD larvae in fruits using the saltwater test and the number of SWD adults in traps baited with apple cider vinegar and a drop of unscented dish soap were counted and recorded weekly on July 21st, 28th and August 3, 2023. Steinernema feltiae products come in pouches of 250 million. Four pouches (1 billion) are needed per acre.
Mixing Steinernema feltiae (SF) with water. Photo by Gary Gao, The Ohio State University.
Spraying Steinernema feltiae (SF) onto the ground beneath the blueberry canopies. Photo by Gary Gao, The Ohio State University.
SWD traps baited with apple cider vineyard and a drop of unscented soap. Photo by Gary Gao, The Ohio State University.
We are still figuring out the optimal timing, method, and rate of application. SWD is quite hard to control due to its short lifespan and multiple generations per year. In blueberry plantings, insecticidal sprays are very difficult to apply without knocking a lot of fruits off. A soil drench or spray with Steinernema feltiae may be one of the tools in the toolbox. We are hoping that a ground based robotic sprayer or drip irrigation can be viable methods of EPN application.
Project Information: RESTOCKING THE IPM TOOLBOX TO MEET INSECT MANAGEMENT CHALLENGES IN HIGHBUSH BLUEBERRY – National Institute of Food and Agriculture CPPM program (Grant No.2020-70006-33015 and Project Number: MICL05122)
Using Laser as a Bird Deterrent in Fruit Plantings
Dr. Gary Gao, Professor and Small Fruit Specialist, CFAES South Centers, The Ohio State University
Laser or laser scarecrows are becoming more and more widely used as a way to deter birds in fruit or vegetable plantings, fish ponds, and commercial buildings. Dr. Gary Gao saw a commercial model being displayed at the trade show of 2023 National Association of County Agricultural Agents annual meeting in Des Moines, Iowa.
AVIX MARK II, a laser bird deterrent produced by Bird Control Group. The company’s website is https://birdcontrolgroup.com/. Photo by Dr. Gary Gao, the Ohio State University.
AVIX Mark II can project a strong green laser beam and can be powered by solar panels or connected to a power outlet. There are a lot of testimonials by people from many different counties. The unit looks quite impressive. However, I do not have any data of my own to validate it. I would love to install a unit at our research center to see how effective it is. I was told that one unit can protect 20+ acres when mounted, installed, and used properly. It is important to use it in conjunction with other methods.
Dr. Gary Gao and Ryan Slaughter have tested a less powerful unit at CFAES South Centers. Our results have not been consistent. There are many reasons for this. One is that our unit may not be strong enough – our green laser beam may not be visible enough during the daytime for birds to see it as a threat. The second reason is that our unit may be shutting off at different times. Third, one unit may not be enough for full control. Two units may need to be installed in different parts of the farm to minimize unprotected space. Fourth, our units may need to be kept on in the evening to prevent birds from roosting at night. There may be other reasons as well – birds are very smart. After a while, the birds may get used to the green laser beam. Distress calls and other bird deterrent methods may need to be used as well to keep birds guessing.
More research is definitely needed to develop a more effective and economical way to reduce bird depredation. Lasers may play an important role in this. What we do know is that something has to be done to help growers!
Upcoming Events:
September 13, 5:30 pm – 8:00 pm, Tools at Twilight: Soil & Water Management Field Day & Demonstrations
September 19 – 21, Farm Science Review
September 27, Wooster, OH, Midwest Mechanical Weed Control Field Day
December 5th – 7th, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo