OSU Plant Disease Diagnostic Services for Commercial Vegetables Will Resume April 13

Septoria leaf spot on tomato transplants

The OSU Vegetable Pathology Lab will resume plant disease diagnostic services in Wooster on Monday April 13 on a limited basis (see below). This service is provided at no cost to Ohio commercial vegetable growers. Dr. Francesca Rotondo will carry out the usual diagnostic procedures during the limited time she is in the lab. If possible, please contact us with digital samples before sending physical samples:

  1. Send photos or short videos that represent the problem via text or email to Dr. Sally Miller (330-466-5249/miller.769@osu.edu) AND Dr. Francesca Rotondo (865-640-5621/rotondo.11@osu.edu).  If we can’t diagnose the problem from the digital samples we will ask you to send a physical sample.  Growers who can’t access/don’t use digital technology should call Dr. Miller or Dr. Rotondo.
  2. No drop-off samples can be accepted. Ship samples Monday through Thursday via overnight delivery (USPS, FedEx, UPS or other courier) to the OSU Vegetable Pathology Lab, c/o Dr. Francesca Rotondo, 234 Selby Hall, 1680 Madison Ave., Wooster, OH 44691 (330-466-5249).

Please see the Vegetable Pathology Lab website before sending samples, for more information and to access the Plant Sample Submission Form.

Freeze / Frost Potential in Ohio – Aaron Wilson, Jim Jasinski

Now that the calendar has turned to April and warmer temperatures are becoming more frequent, those with horticultural interests are eager for the start of the growing season. But April can be a fickle month, with both warm spring rains and lingering cold nights that bring hard freezes and frost and occasionally, even a late-season snowfall. The threat of spring cold temperatures on horticultural production and operations (seeding, transplanting and flowering/fruit) can be greater following early season warmth, where phenological conditions may be advanced for this time of year.

Winter (December 2019 – February 2020) averaged 2-8°F above average compared to the climatological normal (1981-2010; Fig. 1). This warmth continued throughout March as well, with temperatures 4-8°F (west to east) above average. As a result, growing degree day accumulations range from the mid-60s (Ashtabula County) to nearly 200 (Lawrence County) after the first week of April 2020, with our landscapes, fruit trees, and gardening equipment coming to life.

Figure 1: Departure from average (1981-2010) temperatures for December 2019 – February 2020. Figure generated by the Midwest Regional Climate Center (http://mrcc.illinois.edu).

Frost and Freeze Potential

What is Ohio’s typical expectations regarding freeze (≤32°F) conditions in April and May? On average, locations throughout Ohio experience their last seasonal freeze from mid-April (southern Ohio) through mid-May (northeastern Ohio). Timing varies year to year and across Ohio. For a regional analysis, we have selected 8 locations from around Ohio to compare typical last seasonal freeze conditions (Fig. 2).

Figure 2: Selected locations around Ohio for freeze potential analysis displayed in Fig. 3.

Figure 3 shows the probability of experiencing a later freeze in Spring than indicating by the line graphs. All locations show probability based on the most recent 30-year period (1990-2019) except for 7-Lancaster (1996-2019). For each location, five temperatures are displayed (20°F-purple, 24°F-blue, 28°F-green, 32°F-yellow, and 36°F-red). For the purposes of this article we will focus on 32°F and 28°F (considered a hard/killing freeze). The bottom (x-axis) shows the probability that each of these temperatures will occur after a given date (indicated by the left or y-axis).

Figure 3: Probability of a later freeze in the spring for various locations (Fig. 2) around Ohio. Graphs generated by the Midwest Regional Climate Center (http://mrcc.illinois.edu).

Let’s run through an example of how to use Figure 3. For 1-Wauseon, we see that there is a 50% climatological probability of experiencing a 32°F temperature (yellow) after April 27, and this probability decreases to 20% by May 10. The colder, more damaging temperature of 28°F occurs 50% of the time after April 16, with only a 20% chance of seeing 28°F after April 27. For a southern location like 8-Marietta, these dates occur earlier in the season. Here, there is a 50% climatological probability of experiencing a 32°F temperature after April 18 with 28°F occurring 50% of the time after April 2.

Besides latitudinal (north of south) position, what other factors can influence springtime minimum temperatures? Colder air is more dense than warmer air, meaning it wants to remain close to the ground and will flow over the terrain like a fluid to settle in areas of lower elevation. If your location is in a valley or low-lying area, the climatological dates will likely be shifted later to account for more freeze potential later in the spring. Water bodies are typically colder than the surrounding land areas in spring which may keep temperatures in the immediate vicinity a little colder. For 2020, water and soil temperatures are above average, so they are likely to have a moderating impact this year. Cloud cover and higher humidity in the spring will keep air temperatures warmer due to their absorption of terrestrial (from the surface) radiational effects. Finally, late season snowfall combined with clearing skies overnight can also cause the surface to cool rapidly and lead to damaging freeze potential as well. All of these factors should be considered when comparing your location to those selected in Fig. 3.

April 2020 Outlook

At the time of this writing, the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (https://www.cpc.ncep.noaa.gov/) outlook for April 10-20, 2020 calls for increased probability of seeing below average (unseasonably cold air) settling into the Upper Great Plain, Midwest, and Ohio Valley (Fig. 4) with a moderate risk of experiencing much below average minimum (nighttime) temperatures. Given the warm start to the year and current phenological conditions, those with horticultural assets should monitor this freeze potential closely and be prepared to mitigate when necessary to avoid losses. For a weekly climate update, please visit the State Climate Office of Ohio’s website (https://climate.osu.edu).

Figure 4: 8-10-day (April 13-19, 2020) temperature outlook. Figure courtesy of NOAA’s Climate Prediction Center.

Aaron Wilson is a research specialist with the Byrd Polar & Climate Research Center and a climate specialist with the Department of Extension. You can also follow Aaron on social media: @dwweather-Facebook or @drwilsonsWx-Twitter.

Last Call – 2 More Pumpkin or Squash Growers for On-Farm Mustard Biofumigation Trial

Interested in seeing if planting mustard cover crops prior to pumpkins or squash can reduce soil borne diseases and increase your yield? We are looking for 2 more growers preferably in the central or southern part of the state to put out a mustard cover crop (MCC) biofumigation trial to reduce soil borne disease pressure with the following guidelines and conditions. Deadline to sign up is March 19.

Growers requirements and general protocol:
-Growers must plant in field known to have a Plectosporium blight infestation. Growers with fields infested with Fusarium or Phytophthora will also be considered.

-Growers need to have equipment to seed the cover crop, chop (bush hog or flail), incorporate (rototill), pack the soil (culti-mulcher) and possibly seal the soil using a sprayer or irrigation system. These steps will be done in rapid succession so 3 tractors are ideally needed, each hooked to an implement. Don’t have 3 tractors? Maybe borrow one from a neighbor for a few hours?

-Growers will put out 4 strips of MCC and 4 strips without a MCC.

-Strip sizes will be up to 0.1A each for a maximum of 0.8A needed for the entire on-farm study.

-Growers will plant Caliente Rojo, currently the highest yielding glucosinolate mustard available.

OSU will provide:
-The Caliente Rojo seed, the fertilizer (urea + granular ammonium sulfate) and 1K seeds of the hybrid Solid Gold (Rupp).

-We will evaluate each grower site for disease incidence on foliage three times during the season, plus a harvest where mature fruit are weighed and graded for disease.

Study Timeline
-The MCC strip plots fertilizer will be disked into the soil prior to seeding to ensure high biomass production.

-The MCC planting date will be between March 30 and April 30 based on soil conditions and weather forecasts.

-Approximately 50-60 days later, the MCC will be at peak flowering and will be chopped, rototill incorporated into the soil and then packed using culti-mulcher. If irrigation is available, water will be applied to help seal the soil and create a better environment for biofumigation.

-Within 10-14 days of incorporation, Solid Gold pumpkins will be transplanted or direct seeded into those strips at roughly 4ft spacing between plants. Note that transplants are preferred at each site instead of direct seeding. Transplants will lead to an earlier harvest.

Plot Care
Each farm will follow their own standard weed, insect and disease control and fertility practices on the 8 strips. The fungicides used on the crop will need to be discussed ahead of time so we can limit the use of fungicides that might help control Plectosporium blight. These fungicides are Flint, Cabrio, Quadris, Inspire Super and Merivon.

Disease ratings of incidence on vines, foliage and fruit will be taken at 14-21 day intervals from vining until fruit maturity. Sections of all strips will be harvested and fruit will be weighed and graded for disease.

Sign up
If interested in participating in this project or have questions, please contact me at 937-484-1526 or jasinski.4@osu.edu by March 19.

If growers want to see a video detailing the steps and processes involved with planting MCC as a biofumigant, check out the work we did in 2019 at https://youtu.be/Taz-PhDphhA.

This project is being funded by the Ohio Vegetable and Small Fruit Research and Development Program and the IPM Program.

Pumpkin & Squash Growers Wanted for On-Farm Mustard Biofumigation Trial

Plectosporium blight on fruit and handle.

Plectosporium blight on petioles and leaf veins.

In 2019, research was conducted into the use of mustard cover crops as a biofumigant to reduce a specific soil borne disease in pumpkins, Plectosporium blight, also known as white speck or Microdochium. The signs of this disease start out as spindle shaped lesions on the petioles, vines and back of leaf veins potentially killing the plant. If the disease progress, it can infect the handles and turn immature and mature fruit white.

Although our trial in 2019 was planted in a Plectosporium infested field, very little disease developed due to the near drought like conditions at the research station in South Charleston. In wetter locations around Ohio this disease was seen last year and we still think there is potential for this cultural technique to reduce disease in pumpkin and squash fields. To accomplish this on a wider scale in 2020, we plan to replicate and expand our mustard cover crop (MCC) biofumigation study to include on-farm trials with growers.

We are looking to recruit 4-6 growers preferably in the central or southern part of the state to put out a mustard cover crop biofumigation trial to reduce soil borne disease pressure with the following guidelines and conditions.

Growers requirements and general protocol:
-Growers must plant in field known to have a Plectosporium blight infestation. Growers with fields infested with Fusarium or Phytophthora will also be considered.

Equipment needed to successfully manage a mustard cover crop.

-Growers need to have equipment to seed the cover crop, chop (bush hog or flail), incorporate (rototill), pack the soil (culti-mulcher) and possibly seal the soil using a sprayer or irrigation system. These steps will be done in rapid succession so 3-4 tractors are ideally needed, each hooked to an implement.

-Growers will put out 4 strips of MCC and 4 strips without a MCC.

-Strip sizes will be up to 0.1A for a maximum of 0.8A needed for the entire on-farm study.

-Growers will plant Caliente Rojo, currently the highest yielding glucosinolate mustard cover crop available.

OSU will provide:
-The MCC seed, the fertilizer (urea + granular ammonium sulfate) and 1K seeds of the pumpkin hybrid Solid Gold (Rupp).

-Also evaluate each grower site for disease incidence on foliage three times during the season, plus a harvest where mature fruit are weighed and graded for disease.

Study Timeline:
-The MCC strip plots fertilizer will be disked into the soil prior to seeding to ensure high biomass production.

-The MCC planting date will be between March 30 and April 30 based on soil conditions and weather forecasts.

Mustard cover crop at full bloom.

-Approximately 50-60 days later, the MCC will be at peak flowering and will be chopped, rototill incorporated into the soil and then packed using culti-mulcher. If irrigation is available, water will be applied to help seal the soil and create a better environment for biofumigation.

-Within 10-14 days of incorporation, Solid Gold pumpkins will be transplanted into those strips at roughly 4ft spacing between plants. Note that transplants are preferred at each site instead of direct seeding, but if this is not possible, we can discuss options. Transplants will lead to an earlier harvest.

Plot Care:
Each farm will follow their own standard weed, insect and disease control and fertility practices on the 8 strips. The fungicides used on the crop will need to be discussed ahead of time so we can limit the use of fungicides that might help control Plectosporium blight. These fungicides are Flint, Cabrio, Quadris, Inspire Super and Merivon.

Disease ratings of incidence on vines, foliage and fruit will be taken at 14-21 day intervals from vining until fruit maturity. Sections of all strips will be harvested and fruit will be weighed and graded for disease.

The Big Picture:
By expanding the number of sites for this research through on-farm trials, we expect to see the potential MCC may have to reduce the soil borne disease complex affecting cucurbits. By recruiting growers into this process at a small scale, we hope to gain their valuable feedback as to the feasibility and challenges of using MCC on their farm. If successful, growers will spread the news to other growers who might be willing to try MCC on their farm. In addition to the potential biofumigation benefit, growers will be enhancing their soil organic matter levels and provide premium although brief pollinator habitat during flowering.

If growers want to see a video detailing the steps and processes involved with planting MCC as a biofumigant, check out the work we did in 2019 at https://youtu.be/Taz-PhDphhA.

Sign up:
If interested in participating in this project or have questions, please contact me at 937-484-1526 or jasinski.4@osu.edu by March 14.

This project is being funded by the Ohio Vegetable and Small Fruit Research and Development Program and the IPM Program.

Midwest Vegetable Production Guide Now Available

If you are a vegetable grower in Ohio, the Midwest Vegetable Production Guide, is an essential resource to keep on top of the latest fertility, horticultural management, and pesticide recommendations for your operation. Each year the guide is edited and updated by specialist’s in eight states to bring you the most current information possible at the time of printing.

What’s new to the guide in 2020? Within the 262 spiral bound pages there is an updated Organic Production section plus updated sections on disease, weed and insect management on 45+ vegetable crops, from Asian vegetables to Zucchini.

The MVPG is also more mobile friendly now with an improved interface designed to get your crop production question addressed quickly. Enter your crop and pest information and receive cultural and pesticide recommendations matching your request. Try it out on your computer, tablet or smart phone at https://mwveguide.org. The site will default to the new interactive mobile friendly interface but if you want to access individual pdf chapters of the guide, click on the drop down and select “Production Guide.”

MVPG new and mobile friendly interface.

To get a traditional hard copy of the guide, contact your local Extension office and they can order a copy from main campus. Cost will be around $15.

MVPG cover for 2020. 

If you want to order a guide online through the new Extension publications website, here is the link https://extensionpubs.osu.edu/2020-midwest-vegetable-production-guide-for-commercial-growers/. If you order the guide online and have it mailed to your house, it will cost $21.25 plus shipping.

Be sure to purchase your guide soon, there are only 90 copies left in inventory at OSU! Best of luck for a productive season!

 

 

 

Spotted Lanternfly Slowly Approaching Ohio

The Spotted Lanternfly (SLF) is a newly discovered invasive pest from Asia. It is primarily a pest of trees like apples, cherries, black walnut, poplar, maple, tree of heaven and vines such as grapes and hops but it’s not reported to attack most vegetable crops. This pest was first detected in Berks County, PA in 2014, and has since spread to NJ, DE and VA; it has also been observed in MD, NY, CT and NC. In January 2020, new detections were found in western PA bordering Ohio and in eastern West Virginia (Figure 1).

Figure 1. Current known distribution of Spotted Lanternfly.

Damage is caused by inserting large sucking mouthparts into the trunk of the tree or vine and then siphoning out large amounts of sap. Excess sap from either the trunk injury or the planthopper can drip down the trunk and turn dark if infected with sooty mold. No diseases are known to be spread by this insect at this time, but excessive feeding weakens the tree and causes increased mortality during winter.

This pest is a planthopper and as an adult has red and purple wings and nearly one inch long (Figure 2). The immatures resemble stink bugs, being black with white spots when young, and red with black and white spots when older. The overwintering stage is the egg which is laid in masses of 15-30. At this time of the year, the eggs look like elongated brown seeds which can be attached to just about any surface including wood, stone and metal.

Figure 2. Life cycle of Spotted Lanternfly.

While we have NOT seen this pest in Ohio yet, it is within 15 miles of our eastern border and could very likely hitchhike its way into Ohio on a car, truck, trailer, train or boat. If you have tree of heaven on your property, which is one of its favorite hosts, or a vineyard nearby, check the trunks or vines for eggs now or check for nymphs and adults later in the season. If any questionable insects are seen, mark the location, take pictures, and contact your local Ohio State University Extension office or the Ohio Department of Agriculture, Division of Plant Health at 614-728-6400. Do not collect or transport any suspected SLF eggs, nymphs or adults.

For more information and pictures, see USDA’s Pest Alert on this pest: https://www.aphis.usda.gov/publications/plant_health/alert-spotted-lanternfly.pdf

This article was prepared by Jim Jasinski, Dept. of Extension and Celeste Welty, Dept. of Entomology

Mid-Ohio Small Farm Conference “Sowing Seed for Success”


OSU Extension Mid-Ohio Small Farm Conference – Sowing Seeds for Success scheduled for March 14th
Do you own a few acres that you want to be productive but you’re not sure what to do with it?
Do you have a passion for farming and turning your piece of this wonderful earth into a food producing oasis?
Do you own land or forest that you’re not quite sure how to manage?
Do you want livestock but have questions about fencing and forage?
Do you raise or produce products that you would like to market and sell off your farm but you’re not sure how to make it successful?
If you’re asking yourself these questions you should think about attending the 2020 Small Farm Conference – Sowing Seeds for Success on March 14th from 8:00 a.m. – 3:30 p.m. at the Mansfield OSU Campus in Ovalwood Hall.
The campus is just minutes from I-71 and US Rt 30.
Please visit: go.osu.edu/osufarmconference2020 for class and registration details or call OSU Extension Morrow County 419-947-1070.

Produce Safety Alliance Grower Training in Southern Ohio

The Ohio Department of Agriculture, Division of Food Safety is announcing a Produce Safety Alliance (PSA) Grower Training to be held on January 28, 2020 at the Clermont County OSU Extension Office, 1000 Locust St, Owensville, OH 45160. The training will be one day, 9AM-5PM with an hour for lunch(not provided). There is no cost for in state residents, $85 for out of state. Regulation excluded and exempt growers are also welcome to register for the training.

The PSA Grower Training Course is one way to satisfy the FSMA Produce Safety Rule requirement outlined in § 112.22(c) which states ‘At least one supervisor or responsible party for your farm must have successfully completed food safety training at least equivalent to that received under standardized curriculum recognized as adequate by the Food and Drug Administration.’

The course will cover basic produce safety; worker health, hygiene, and training; soil amendments; wildlife, domesticated animals, and land use; agricultural water (both production and postharvest); postharvest handling and sanitation; and developing a farm food safety plan. As a participant you can expected to gain a basic understanding of: microorganisms relevant to produce safety and where they may be found on the farm; how to identify microbial risks, practices that reduce risks; how to begin implementing produce safety practices on the farm; parts of a farm food safety plan and how to begin writing one; and requirements in the FSMA Produce Safety Rule and how to meet them. There will be time for questions and discussion, so participants should come prepared to share their experiences and produce safety questions.

To receive a completion certificate, a participant must be present for the entire training and submit the appropriate paperwork to their trainer at the end of the course.

Registrations to be submitted by January 17, 2020 (ASAP):

Email: Jordyn.Brown@agri.ohio.gov

Fax: (614) 644-0720

Phone: (614) 728-6250

Mail: Ohio Department of Agriculture

Division of Food Safety – ATTN: Jordyn Brown

8995 E Main St

Reynoldsburg, OH 43068

If you have any questions, please feel free to contact me at (614)600-4272 or mfout@agri.ohio.gov.

Regards,

Matt Fout

Produce Safety Manager, Division of Food Safety

Ohio Department of Agriculture