Research newly Completed and Started

High tunnel studies are affected by weather. However, typically, high tunnel work continues when some operations in open field production are halted. Like growers, the Vegetable Production Systems Lab (VPSL is transitioning to full “summer mode” as conditions allow. See the six panels below for snapshots of a portion of our recent and near-term activities and don’t hesitate to contact us for more information or if we can assist another way.

Matt Kleinhenz (kleinhenz.1@osu.edu; 330.263.3810)

Growers and Researchers continue to Study Grafted Vegetable Plants

In Ohio, full-time study of grafted vegetable plants as products (i.e., sources of income) and production tools began more than ten years ago. Much has been learned and the popularity of grafted plants continues to trend upward. However, growers and researchers continue to ask many large, detailed, and tough questions about the roles of grafted plants in commercial production going forward. “Do grafted plants pay?” may be the most often asked and significant question. This brief article cannot address that question definitively for all readers due to the specific circumstances of each farm, field, crop, planting, season, etc. However, peoples’ collective understanding of the pros and cons of using grafted plants and of conditions leading to a good return on investment after using them is improving. As it does, success with grafted plants improves and their use increases. Regardless, additional research is needed. The three panels below briefly summarize a portion of the vegetable grafting research underway in Ohio in 2019. Please contact us if you would like to learn more about this work and stay tuned to VegNet and other outlets for updates.

Matt Kleinhenz, ph. 330.263.3810, email kleinhenz.1@osu.edu

SPRING ROLLER COASTER RIDE COMING – Jim Noel

It is spring and with it often comes wild swings. This is what we expect for the rest of April 2019.

 A parade of storms will begin later this Thursday into Friday and follow every 3-5 days. This will cause 2-3 inches of rain on average for Ohio the next two weeks as shown in the attached graphic. Normal rainfall is now almost 1 inch per week. Hence, slightly above normal rainfall is expected. The one exception could be northern and northwest Ohio where it is possible to see less rainfall depending on the exact storm tracks.

We are also fast approaching our end of the freeze season typically in mid April up to around the 20th for much of the state. Some places in the north it can be late April. Right now, everything looks like a normal end to the freeze season. We do see the possibility of another freeze this weekend on Sunday AM especially north of I-70. A few more could happen into the next week or two before coming to an end.

Temperatures are expected to overall be slightly above normal for the rest the rest of April but with wild swings. This should help bring 2-4 inch soil temperatures into the normal range, possibly a degree or so above normal. The exception would be northern Ohio where above normal ice levels this past winter on the Great Lakes will keep water temperatures on the Lakes lagging and may keep air temperatures closer to normal there.

With all the storms lined up, we do expect a windy April as well. Winds of 30-40 mph with gust to 50 mph can not be ruled out Thursday or Friday this week with storm number one. 30-40 mph winds will also be possible with the storm later Sunday into next Monday and can not be ruled out with the third storm later next week.

After a wetter April indications are for a warmer and not as wet May with the possibility of normal or even a bit below normal rainfall.

Early indications for the summer growing season are normal or slightly above normal temperatures and possibly a bit wetter than normal though June could be a bit drier.

https://www.weather.gov/ohrfc/SeasonalBriefing

Other early indications give the possibility of another wet harvest season.

National Weather Service
Office:
1901 South State Route 134, Wilmington, OH 45177
Phone:
937-383-0430
Specialization:
Weather, Flooding, Climate impacts
Biography:

Jim Noel is currently the Service Coordination Hydrologist at the NOAA/National Weather Service’s Ohio River Forecast Center (OHRFC). He started in the National Weather Service in 1992 and has been with the OHRFC since 1996 as a hydrologist.

Grower, Gardener, Educator, and Researcher – All can Gain from Vegetable Grafting

Grafting is an ancient technology currently coming of age, helping vegetable growers and gardeners and educators and researchers in Ohio and the U.S. address some of today’s most significant challenges. Find out more at two upcoming programs.

The Muck Crops School on January 10 in Willard, OH will include a presentation by grafting expert Dr. Richard Hassell of Clemson University. He will outline progress made in developing rootstock (RS) varieties resistant to Phytopthora capsici, a devastating disease of pepper, tomato, melon, and other major vegetable crops. In grafting, root systems of RS varieties are spliced to the shoots of scion varieties, creating physical hybrids that often out-perform ungrafted versions of the scion variety, especially under stressful conditions. Indeed, creating physical hybrids opens key opportunities in production, research, and education. Contact OSUE-Huron County (https://huron.osu.edu/home) about attending the Muck Crops School on Jan 10, 2019.

The Ohio Produce Network program on January 16-17 in Dublin, OH will include two sessions on grafting, both occurring on January 16. Session 1 will feature presentations and discussion led by six additional experts: Dr. Chris Gunter (NCSU), Dr. Matt Kleinhenz (The OSU), Dr. Sally Miller (The OSU), Cameron Way (Way Farms), Chuck Mohler (Sweet Corn Charlie Farms), and Ed Kerlikowske (http://lifegivingfruit.com/). A representative of TriHishtil (http://www.trihishtil.com/), a major supplier of grafted plants, may also participate. Together, the six presenters and discussion leaders will provide a comprehensive, up-to-date, and stakeholder-focused summary of grafted plants as sources of income and production tools. Session 2, later on Jan 16, will deliver individualized training in making grafted plants, a straightforward process that can be completed in many settings. See http://www.opgma.org/ohio-produce-network/ about attending the OPN on Jan 16-17, 2019.

Contact Matt Kleinhenz (330.263.3810, kleinhenz.1@osu.edu) for additional information about these programs and see http://www.vegetablegrafting.org/ and http://u.osu.edu/vegprolab/research-areas/grafting-2/ for more information about vegetable grafting.

Biodegradable Mulch: Your Next Production Tool?

Vegetable extension-research personnel from Ohio, Kentucky, Tennessee, and Iowa met on October 5, 2018 to discuss ongoing work and to plan follow-up activities … all toward helping improve short- and long-term farm success. Biodegradable mulch (BDM) was among the most talked-about topics. Dr. Annette Wszelaki of the Univ. of Tennessee led the BDM discussion and she provides comments for VegNet readers below. Also, note that Dr. Wszelaki will expand on these comments and summarize the large amount of research that her and other teams in various states have been doing with BDM, including on commercial farms, at the OPGMA-led Ohio Produce Network Meeting in Dublin, OH in January-2019. That presentation will be an excellent opportunity to gain a thorough update on BDM and its possible place in your toolbox.

Comments and Photos by Dr. Annette Wszelaki, Professor and Commercial Vegetable Extension Specialist, Univ. of Tennessee

Plastic mulches provide many advantages for vegetable production, such as weed and disease management, earliness of harvest, increased yield and quality, and moisture retention. However, plastic mulch use is not without disadvantages, including the cost, labor and environmental issues associated with plastic mulch disposal. Biodegradable mulches (BDMs) offer a potential alternative if they can provide similar advantages to plastic mulch without the disadvantages.

BDMs can look similar to traditional polyethylene mulch (i.e., stretchy and black or white-on-black) or in the form of paper (brown or black, sometimes with creping to give it stretch). They can be laid with a standard mulch layer. BDM’s are designed to cover the soil during the production season, and then begin to degrade as harvest nears. At the end of the season, BDM’s can be tilled directly into the soil. There they will degrade into carbon dioxide, water, and the bacteria and fungi that eat them. The degradation rate varies depending on environmental conditions, but by spring, most remnants will have disappeared.

At the University of Tennessee, we have been working with BDM’s on a variety of crops (tomatoes, pumpkins, and peppers) for 10 years. We have found comparable yields and quality to traditional plastic mulch with these crops, but not all biodegradable mulches and crop responses are equal!

Want to learn more about biodegradable mulches? Come to the session Could biodegradable mulches replace plastic in your production system? at the 2019 Ohio Produce Network in Dublin, January 16-17, 2019. In the meantime, please contact Annette Wszelaki (annettew@utk.edu or 865.974.8332) or visit www.biodegradablemulch.org for more information. Many thanks to Jenny Moore, Jeff Martin, the East TN Ag Research and Education Center Farm Crew, and many students along the way for their contributions to this project.

Figure 1. Creped paper biodegradable mulch just after field laying.

Figure 2. Stockpile of polyethylene plastic mulch on a Tennessee tomato farm.

Figure 3. Biodegradable plastic mulch in the newly planted pepper field.

Building a Shared Understanding of Soil Balancing

Everyone would welcome a holistic, reliable, and relatively straightforward way to enhance and maintain soil health on many farms, regardless of their size, product, management approach (conventional, organic) and other characteristics. Some farmers and consultants have long said that Soil Balancing (SB) is that way, a means to loosen and enliven soil, provide essential nutrients, limit weed problems, and enhance crop yield and quality. However, university researchers have largely been unable to support that overall claim or recommend Soil Balancing as the guiding philosophy when making soil, fertility, weed, and certain crop management decisions. With USDA support and the help of many growers, consultants, and others in the industry, an OSU team has been taking another look at the situation, possibly the most comprehensive, collaborative, and long-running evaluation to date.

As outlined in three previous VegNet articles and other references on SB, the philosophy calls for achieving an optimum ratio of calcium, magnesium, and potassium in the soil. This may require large amounts of limestone and/or gypsum and multiple years to “move the needle” on soil chemistry, physics, and biology (and their follow-on effects on weeds and crops) in a positive direction. Regardless, some see the payoff as significant. Importantly, evaluating the economics of Soil Balancing is one component of the OSU-led effort, which began in 2015 and is set to provide valuable new insights. Look for summaries in upcoming publications, programs, and other resources.

A Stakeholder Advisory Committee including farmers, consultants, and university professionals from Ohio and other states has guided the OSU team throughout its work, helping to design experiments and interpret and share findings. Committee members and others visited project research plots on farms near Wooster and at the OARDC and discussed project emerging project findings on August 9 and 10. In this picture, the group discusses the status of plots containing butternut squash, edamame soybean, and dwarf popcorn. For more information, see https://u.osu.edu/vegprolab/research-areas/soil-balancing/ or http://organicfarmingresearchnetwork.org.ohio-state.edu/network_activities/soil_balancing/ or contact Matt Kleinhenz (330.263.3810; kleinhenz.1@osu.edu).

They’re back…Japanese beetles on the rise

This article was written to complement Celeste Welty’s blog on Japanese beetle insecticide selection last week (http://u.osu.edu/vegnetnews/2018/06/30/insecticide-notes/).

One of Ohio’s most recognizable leaf feeders, the copper-colored and metallic green Japanese beetle, is on the rise. According to scattered reports across the state, this beetle has been leaving a trail of skeletonized leaves on an array of landscape plants, field crops, vegetable and fruit crops.

 

Japanese beetle adult.

While specific thresholds do not exist for most crops, below are listed a few guidelines that should help growers manage Japanese beetles in general.

Silk clipping.

Sweet Corn – During the early-silking stage, examine 50 ears in small plantings (< 2 acres) or 100 ears in large plantings (> 2 acres). Treat by spraying insecticide directed at the silks to prevent clipping by beetles during the early-silk stage if the average number of beetles is 2 or more per ear.  If pollination has already occurred, silk clipping will not harm kernel development or ear, therefore control is not necessary.

Hops – At this time there is no established treatment threshold for Japanese beetles in hops. Growers should consider that established, unstressed and robust plants can likely tolerate a substantial amount of leaf feeding before any negative effects occur. Those managing hopyards with small, newly established, or stressed plants should take a more aggressive approach to Japanese beetle management, as plants with limited leaf area and those already under stress will be more susceptible to damage. It is also important to carefully observe beetle behavior in the hopyard; if flowers, burrs or cones are present and being damaged, growers should consider more aggressive management as yield and quality are directly affected (excerpted from https://www.canr.msu.edu/uploads/234/71503/Hop_JapaneseBeetle.pdf).

Fruit crops and Grapes – For most fruit crops, there is no economic threshold on the number of beetles or amount of damage that requires treatment. If a susceptible cultivar is being grown and growers previously have experienced high populations of Japanese beetles, an insecticide should be applied when beetles emerge and thereafter as needed.

Feeding damage on raspberry.

A Japanese beetle lure and trap is available for monitoring this pest, however these beetles are easily detected while walking through the planting. If skeletonizing of leaves or feeding on the fruit becomes evident, the plants may need to be protected with an application of insecticide. The usual threshold for making a spray application is about 15% of the leaves damaged with adult beetles still present (excerpted from http://extension.missouri.edu/sare/documents/MidwestSmallFruitPestManagement2012.pdf).

Remember to consult the Midwest Fruit Pest Management Guide 2018 (https://ag.purdue.edu/hla/Hort/Documents/ID-465.pdf) for specific management details about this pest on apples, brambles, peaches, plums, grapes, and blueberries including pesticide recommendations. This resource is rich with details for each crop concerning insecticide group, product selection and efficacy, REI, PHI, and small tips to aid in control.

For help on insecticide selection on vegetable crops, consult the Midwest Vegetable Production Guide 2018 (https://ag.purdue.edu/btny/midwest-vegetable-guide/Pages/default.aspx).

Spray Drift 102

A few weeks ago, in Drift 101, I suggested that farmers should be cautious before concluding that sick crops are a result of herbicide drift from neighboring fields. Symptoms attributed to drift may be caused by other factors. Nutrient deficiencies may cause chlorosis (yellowing) and necrosis (tissue death), symptoms easily misinterpreted as resulting from herbicide exposure (https://vegnet.osu.edu/sites/vegnet/files/imce/newsletters/VegNet/5-31-16%20VegNet%20Vol%2023%20Issue%207myedits.pdf).

The herbicides 2,4-D and dicamba invariably cause distorted growth of foliage (Figure 1), but so can various environmental pollutants especially when those are concentrated in the greenhouse (Figure 2).

Figure 1: Typical response of tomato foliage to low-dose (simulated drift) of 2,4-D.

Figure 2: Distorted growth of greenhouse tomato thought caused by fumes from incomplete combustion from wood heater. Photo courtesy of M. Badertscher (OSUE Hardin Co).

Likewise flood conditions, during which root systems are completed saturated with water for prolonged periods, are known to induce leaf twisting and formation of adventitious roots (Figure 3), symptoms associated with exposure to 2,4-D (Figures 1 & 4).

Figure 3: Adventitious root formation on stem of tomato following 3 days of flooding conditions (root zone saturation).

Figure 4: Adventitious root formation on stem of tomato following exposure to low-dose 2,4-D.

Even when herbicides are the cause, symptoms can occasionally be misleading and point incorrectly to a nearby field. Consider the case of glyphosate, still the most commonly used herbicide in the Midwest. Glyphosate is quickly absorbed by crop leaves and translocated to growing points. On most crops glyphosate damage becomes obvious 4 or more days after drift because new growth is chlorotic. On tomato, chlorosis most often appears as bands across the base of the leaflets (Figure 5). However in a small number of drift events, chlorosis may not appear at all; instead glyphosate induces leaf and petiole curling and twisting, symptoms reminiscent of 2,4-D or other synthetic-auxin herbicides.

Figure 5: Characteristic basal-chlorosis of new tomato leaflets caused by glyphosate drift.

Figure 6: Occasional ‘auxin-mimic’ symptoms that occur in a small percentage of glyphosate drift events.


Soil residues of environmentally persistent herbicides used in previous growing seasons must also be taken into account. Trace amounts of herbicides in the ALS and AHAS families can cause symptoms similar to those caused by 2,4-D and dicamba. Imazethapyr (Pursuit) is an AHAS herbicide used on soybean that controls weeds at low doses of 3-6 oz/Acre. In our lab, tomato flowering was sensitive to doses of the herbicide equivalent to 1/1000th of the field dose. This finding indicates that soil residues of imazethapyr applied two or more years before planting may still be sufficient to injure field grown tomato, as may drift of the herbicide from a nearby or not-so-nearby application.

Many more similar examples could be provided; hopefully, the take home message is that diagnosing crop injury symptoms is a complicated matter that must take several factors into consideration and can easily lead to mistakes being made. Tread cautiously.

Spotted Wing Drosophila Workshop – April 5th

The spotted wing Drosophila (SWD) was first observed in Ohio in 2011.  This tiny fly is now a major pest of small fruit (strawberries, raspberries, blackberries, & blueberries), grapes, and peaches for anyone producing these crops from backyard to commercial scale growers throughout Ohio. What makes this vinegar fly different from other related flies is it attacks healthy uninjured ripening and ripe fruit, not old or damaged fruit like other flies.

So what is the best way to learn how to identify, monitor, and manage SWD? By attending our SWD workshop where these topics will be tackled one by one, including how to use a stereoscope to see these flies up close, how to properly use and service the SWD traps, and how to manage the pest once it arrives at your farm (see flyer below). The meeting has been scheduled from 9am-noon on April 5th at the Washington County Extension office, located at 202 Davis Avenue, Marietta, OH 45750.

Growers from anywhere in Ohio can attend, but due to space limitations, we can only accept the first 20 growers who apply, so be sure to register for this workshop by March 29th. There is a $10 fee to attend the workshop which will be collected at the beginning of the workshop to cover refreshments and snacks. Click on the link below to sign up for the class.

https://www.surveymonkey.com/r/SWDReg18

All attendees will receive one Scentry SWD Trap and 1-2 Scentry SWD lures to help get you started monitoring for this pest, along with vials filled with male and female SWD to use as reference specimens.

If you have any questions about the workshop, please contact Jim Jasinski (jasinski.4@osu.edu) or Marcus McCartney (mccartney.138@osu.edu). This workshop is sponsored by the OSU Dept. of Entomology, Dept. of Extension IPM Program, and USDA NIFA.

 

 

 

 

Pumpkin Hybrid Review – 2017

In an effort to help growers select and grow the best pumpkins for their operation, the Integrated Pest Management Program planted a demonstration trial at the Western Ag Research Station in South Charleston to highlight foliage, handle, fruit size, and fruit quality. There were 20 entries from four companies in the trial, with emphasis placed on hybrids that offered some type of disease resistance, primarily to powdery mildew. The intent of the trial was primarily for growers who attended the pumpkin field day to observe differences in plant and fruit quality in person, in order to generate a visceral opinion and appreciation for the hybrid.

The trial was originally direct seeded June 1st, but due to mice damage and flooding rains, was replanted with transplants June 16th. Approximately 75 pounds of nitrogen was side dressed as liquid 28-0-0 on June 9th, with no P or K applied per soil test recommendations. Strategy and Dual were used pre-emerge to control weeds, with shielded applications of glyphosate followed by hoeing and hand weeding throughout the season. Once powdery mildew was detected in these plots on July 24th, they were sprayed on a 7-10 day schedule with a standard fungicide program that alternated several modes of action, per OSU recommendations.

While specific trial data was collected, because it was not replicated or randomized, all calculations for yield and fruit size should be seen as estimates taken from one site, under a specific set of weather conditions. When making decisions about hybrid selection for 2018, this information should be combined with other trial data from around the state or region. This trial was not irrigated, and received above average rain fall for this location based on historical records.

Group shot of pumpkin hybrid trial, large fruit in top row, medium sized fruit in middle row, and small fruit in bottom row.

To obtain average fruit weight, 3-5 fruit of each hybrid per plot representing the largest, smallest, and average sized fruit were chosen and weighed. All other marketable fruit in plot were counted and used in yield calculation, which was based on a 15’ row spacing, 35’ length of row, with plant spacing 3-4’ apart.

If you have additional questions about the trial, contact me directly at jasinski.4@osu.edu.

Yield data from pumpkin hybrid trial, see above for yield estimates. *indicates reduced stand in trial.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Seed companies and other pumpkin hybrid attributes from 2017 trial. PMR = powdery mildew resistant, PMT = powdery mildew tolerant.