As I write this article on Monday afternoon, showers and a few embedded storms are rolling across the Buckeye State. However, for southern and southeastern Ohio, this has largely not been the case for the last several weeks. Precipitation over the past 30-to-60-days is running 25-75% of normal, with some parts of Pickaway, Ross, Noble, Morgan, Washington, Monroe, and Belmont Counties receiving less than 2 inches over this period (Figure 1). As a result, the latest US Drought Monitor depicts about 8% of Ohio in D2-Severe Drought and abnormally dry conditions or worse being felt by
approximately 70% of the state. This has led to notable crop stress on drier ground, deep cracks in the ground from the lack of soil moisture, poor pasture conditions, and short-cuttings of hay. Producers are encouraged to provide observations from their locations by submitting a Condition
Scattered showers and storms are possible on Tuesday through Thursday this week, before high pressure and drier air moves in for the weekend. However, widespread heavy rain is not expected. The Weather Prediction Center is currently forecasting 0.01-0.50” for the state over the next 7 days (Figure 2), though locally heavier amounts are possible. Temperatures will generally rise into the low to mid 80s each day with overnight lows in the 60s, about average for mid to late July.
The 8-14 day outlook from the Climate Prediction Center and the 16-Day Rainfall Outlook from NOAA/NWS/Ohio River Forecast Center show temperatures are likely to be above average with precipitation probability leaning toward wetter than average (Figure 3). Climate averages include a high-temperature range of 83-86°F, a low-temperature range of 60-66°F, and weekly total precipitation of 0.90-1.20”.
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.
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:
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.
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
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.
Onions
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.
Fruit
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.
Just like folks who wish for rain or look for irrigation during dry times, growers experiencing more than optimal rainfall look for ways to handle soggy conditions.
Rain is obviously good but too much of it can be a huge headache or worse. While rainfall in some areas has been just about right in recent weeks, rainfall in other pockets of Ohio vegetable production has become troublesome lately.
Open field growers can prepare only so much for excess rain, especially when it falls in large amounts over short periods of time. However, predictions indicate that doing what is possible to prepare for deluges will be useful. Five steps familiar to most experienced growers because they always support positive production outcomes – not just during wet periods or seasons — can help.
1. Use a set of varieties ranging in maturity and seed/transplant multiple times (stagger plantings). This helps manage workloads, blanket market opportunities, and distribute risk since individual plantings will be at different stages in development when dry, wet, or other unwelcome conditions occur and, therefore, possibly be less affected by them.
2. Select naturally well-draining fields whenever possible. Fields that tend to hold moisture may be a blessing during dry periods but a problem during wetter ones. Assuming irrigation is available, naturally well-draining fields are likely to be more reliable across seasons.
3. Improve and maintain the site’s drainage, i.e., its capacity to withstand and “process” excess rain. Grade, tile, and employ rotations and soil management and production practices proven to limit the site’s potential to flood and for saturated conditions to persist.
4. Use appropriate crop-specific tactics to manage beds or hills from the start of each production cycle. Potato, Cucurbit, and other crops are often in direct contact with the soil. So, they can benefit from hills and beds being set and managed as if flooding is a real possibility.
5. Prepare for harvest in advance. Advanced preparation can help ensure it will be possible to harvest sooner than expected, if possible and needed.
A hybrid pumpkin and squash hybrid trial was planted in the Western Ag Research Station in South Charleston, OH. There were 29 hybrids evaluated in the trial ranging from traditional jack-o-lantern fruit to more colorful or textured fruit from a variety of companies as seen in this group photo (Figure 1). The trial focuses on demonstrating foliage tolerance to powdery mildew as well as observing general plant health and growth patterns. A second function of the trial is to evaluate hybrid fruit size, shape, color, etc. and to obtain some estimates of yield and fruit numbers per acre based on our production methods. As these methods are likely to change from grower to grower, so will expected yields and fruit numbers. This report is only to provide an estimate of yield and fruit potential.
Figure 1. Group shot of pumpkin and squash fruit in 2021 trial.
Each plot in the trial was 50’ long and planted on 15’ row centers. There was no replication of the plots, so all data was collected from one plot. The trial was direct seeded on June 1 but nine hybrids were transplanted on May 27 due generally to later maturities so that all fruit would be mature by the pumpkin field day on August 26, which was successfully accomplished. In-row plant spacing was set at 3.5’ for all hybrids.
Harvest and fruit number data were collected on September 2 as all plots showed 95+% mature fruit. Three to five representative fruit were clipped and weighed from each plot, with all other remaining mature and immature fruit in each plot counted. Estimations of yield and fruit numbers for each hybrid are based off of 50’ row plots (0.017A) extrapolated out to a full acre.
For weed control, Strategy (4pt) plus Dual (1.3pt) plus glyphosate (32oz) per acre was applied pre-emergent followed by Sandea (1oz/A) between the rows prior to the vines running. Based on soil sampling no P or K was applied but ca. 75 lb N was sidedressed on using 28-0-0 on June 15.
For powdery and downy mildew control we began applying fungicides July 22 on a 7-14 day schedule following proper rotation guidelines, with the last application being made on August 30. Spray applications were made at 36 GPA at a pressure of 65 PSI using hollow cone nozzles.
Below are listed the basic information and some general notes about each hybrid in the trial listed alphabetically (Table 1). All yield and fruit number data are in Table 2, listed alphabetically by hybrid name.
Table 1. Basic information about hybrid entries including seasonal notes.
Table 2. Estimated yield and fruit count data for 2021 trial.
If you have any questions about the trial, please feel free to contact Jim Jasinski, Jasinski.4@osu.edu.
IR-4 (https://www.ir4project.org/) is conducting their biannual Specialty Crop Growers & Extension survey to assess what disease, pest, and weed problems growers have a difficult time managing because they do not have sufficient management tools.
If you aren’t familiar with IR-4, we have included a link to their website above to learn more.
The deadline to complete the survey has been extended to September 1, 2021.
Emily Justus is a PhD student at Purdue University working on documenting the use of insect resistant hybrids or varieties as part of an overall IPM strategy. If you have a few minutes to share your practices with her that would be very useful for her research program.
Calling all vegetable growers!Please help us learn about how you manage insect pests. I am an entomology graduate student at Purdue University and was awarded a grant from North Central Region – Sustainable Agriculture Research and Education program to investigate vegetable grower pest management strategies. My goal is to understand how vegetable growers in Ohio manage their insect pests and use of integrated pest management strategies such as resistant varieties. Responses from carrot, celery, parsley, celeriac and dill growers would be helpful but all are encouraged to respond. I hope that this work will help extension educators serve you better!
The survey (link below) should take less than 10 minutes to complete and you can enter to win a hard copy of the Midwest Vegetable production guide! Thanks so much for your help!
We are less than 13 days away from the 2021 in-person pumpkin field day on August 26 at the Western Ag Research Station (7721 S. Charleston Pike, S. Charleston). We will have two hours of presentations plus time for growers to roam the plots and see what interests them, including the powdery mildew fungicide trial, pumpkin and squash hybrid trial, and weed control plots.
The field day starts promptly at 5:30 PM where we will have Dr. Aaron Wilson from OSU talking about weather impacts on pumpkin production and Tony Dobbels reviewing a weed screen plot with 10 herbicide treatment combinations of Reflex, Sandea, Dual Magnum and Strategy. For diseases, we were very fortunate to pry Dr. Dan Egel from Purdue University to speak about disease control in pumpkins. Jim Jasinski will briefly cover the pumpkin and squash trial and powdery mildew fungicide trial. After the presentations the participants will be allowed to move around the plots. The field day will end at 7:30 PM.
Cut-off for pre-registration will be Aug. 24. No walk in registration will be possible. Social distancing and mask wearing might be required for the outdoor event so come prepared. No beverages will be provided so bring your own.
Weed Control Video on IPM YouTube
Tony Dobbels talks about weed control in pumpkins and squash
For growers who are unsatisfied with their early and mid-season weed control in pumpkin and squash, take 15 minutes and check out this new pre-emergent herbicide video narrated by Tony Dobbels, Department of Horticulture and Crop Science. In the video, Tony reviews 10 herbicide treatments and combinations of Sandea, Dual Magnum, Strategy and Reflex (currently under a 24c label) and gives his thoughts on their level of control and fit for overall pumpkin and squash production. Watch the video here: https://youtu.be/NmSX4FqK7T4
Powdery Mildew Beginning to Roll
After what seemed like a slower than average start to the powdery mildew season (at least at the research station), leaves in the untreated checks have been climbing to between 50-75% coverage. Be sure to treat on a 7-10 days schedule and use proper FRAC number rotation to reduce the incidence of fungicide insensitivity. Sally Miller’s article on July 10 (https://u.osu.edu/vegnetnews/2021/07/10/addendum-more-powdery-mildew-fungicides-for-cucurbits/) is a great resource to what has been working lately in Ohio and is a must read as we approach the mid point of the disease management season.
Pumpkin Insects Report
For the most part squash vine borer has died down for the season. I saw some extensive damage in the Hardin County crop walk a few weeks back in zucchini but haven’t seen it in any of my pumpkin or squash plantings at the station, although I have been actively catching adults until about two weeks ago.
Cucumber beetles are still hanging out in the flowers but as we approach 100% orange in some of our trials, fewer and fewer flowers are being produced so I expect a switch soon to possible rind feeding. If you are in a similar situation, keep an eye on flower production and where the beetles are actively feeding to avoid rind damage which could lower market quality.
Mating squash bugs.
So that leaves squash bugs as the only insect I see at the station beginning to increase fairly steadily, with many egg masses being detected on leaves, followed by gray nymphs typically aggregated together and eventually larger brown adults. These pests have sucking mouth parts and can feed extensively on the petioles, vines and fruit, sometimes causing collapse. If there are over one egg mass per planting, treatment of the emerged nymphs is easier than waiting for them to become adults. Only treat if necessary to avoid aphid explosions with their accompanying honey dew and black sooty mold on leaves and fruit.
Research and demonstration plots are slowly going in as rain dances across the experiment station in South Charleston. On Tuesday a herbicide screen featuring common products (Strategy, Sandea, Dual Magnum) plus various Reflex treatments were planted. According to the 24(c) label, Reflex is known to have potential phytotoxic reactions with some butternut and squash hybrids, so a sensitivity trial with four butternut squash hybrids, four squash hybrids and two pumpkin hybrids was also planted. Both trials were sprayed on Wednesday, followed by 0.7 inch rain which should have activated all the pre-emerge herbicides. These trials will be rated for weed control and phytotoxicity several times in the next month.
Missing Pumpkin Acres – Partially Solved
Missing pumpkin acres?
On April 2, an article was posted on the OSU VegBlog that looked at the sudden drop of pumpkin acreage from 2015 (>6,000A) to 2016 (<4,000A). I gave a few ideas for the potential drop in acreage and asked growers if they had any thoughts on the matter. I received several email and phone calls about the subject, here is the summary of our discussion.
–Imports: Pumpkins are being imported from other countries or other states more cheaply than they can be produced here in Ohio, so growers who couldn’t compete with the prices of imports got squeezed out of the business.
–Buyers: Many buyers of large chain stores are shopping around for the lowest price possible which has strained traditional supplier relationships. As a result, fewer Ohio growers are willing or able to compete at the lowest possible price so they are not supplying these market needs.
–Labor: It is getting more difficult to find the labor needed to plant, maintain and most importantly harvest and pack a pumpkin crop in a timely manner. This labor used to be local folks or high school kids but that is getting tougher to find, as is qualified migrant labor.
All of these factors and undoubtedly others have contributed to the loss of pumpkin acreage in Ohio. What remains most interesting is the confluence of these factors between 2015 and 2016 to generate a nearly 2,500A loss, which has still not rebounded five years later.
More Cucurbit Pests About to Get Active A few weeks ago I mentioned options for controlling early season cucumber beetles and by extension, bacterial wilt. As we look past the beetle
Squash Vine Borer Video Released on OSU IPM YouTube Channel.
invasion, remain vigilant for squash bugs and squash vine borer. A new video describing how to identify, monitor and manage Squash Vine Borer has just released on the OSU IPM YouTube channel. https://youtu.be/KIHeMtkF98Y
Additional points that could have been made in the video include:
-An alternative to shaking the insects from the trap top into the plastic bag is to have a spare top, so that the active bag can be stuffed into a freezer to kill the contents which makes sorting and identifying much easier.
-The trap bottom should be about one foot above the ground and the string that holds the lure needs to be taught across the bottom of the trap to maximize catch. Use of a thin wire to hold the lure will help prevent sagging. The traps and pheromone lure can be found at just about any insect trapping supply business such as Great Lakes IPM.
-For non-chemical management row covers may work better on some crops than others based on how quickly they flower. There is also the possibility of late planting and/or trap cropping as a means to avoid peak SVB flight provided it fits with your marketing plans.
-While some plants do succumb to SVB attack, many other plants infested with SVB larvae survive and continue to produce fruit.