Corn Newsletter : 2018-04

  1. Corn Newsletter Reader Survey – Reminder

    Author(s): Amanda Douridas

    We’d like to thank all of you who have completed the survey so far. The response has been great. We would still like to hear from those of you who have not completed yet. Our goal is to provide farmers and consultants with accurate, researched based information that helps improve farm efficiency, profitability and sustainability. Completion is voluntary. All survey responses are anonymous and cannot be linked to respondents. Only summary data will be reported. You can complete the survey by going to:

    Thank you again for your time and feedback as we strive to meet the needs of our readers.

  2. Eliminating marestail as a determiner for postemergence soybean herbicide selection

    Author(s): Mark Loux

    Soybean herbicide systems have evolved back to a fairly high level of complexity to deal with the herbicide resistance we have in various broadleaf weeds. By the time we use a comprehensive mix of burndown and residual herbicides, we tend to be coming back with postemergence herbicides primarily for marestail, ragweeds, and waterhemp (and grasses). Postemergence tools available for control of these broadleaf weeds vary with the type of soybean trait being used, but can include glyphosate, PPO inhibitors (fomesafen, Cobra), glufosinate, dicamba, and soon 2,4-D choline. ALS inhibitors have become somewhat irrelevant on these weeds due to widespread ALS resistance, although they may have activity on some ragweed populations still sensitive to ALS inhibitors. Resistance to various sites of action can further limit the number of options.

    The following generalizations about resistance seem appropriate at this time:

    Marestail – almost all populations resistant to glyphosate and ALS inhibitors

    Common ragweed – populations is some areas/fields are resistant to glyphosate and ALS inhibitors, and in some cases also PPO inhibitors. Other populations still largely respond to all of these herbicides

    Giant ragweed – most populations have lost sensitivity to glyphosate and some are resistant. Many populations also resistant to ALS inhibitors, especially if they have glyphosate resistance. No confirmed PPO resistance yet.

    Waterhemp – all populations resistant to ALS inhibitors, most resistant to glyphosate, some resistant to PPO inhibitors also. Resistance is more widespread in areas/fields with longest history of waterhemp problem

    In soybeans, we assume that regardless of the residual herbicides used at planting, giant ragweed and waterhemp will require postemergence herbicides. The same can be said for common ragweed that has resistance to ALS inhibitors – flumioxazin can provide some residual control of these populations but not to the point that postemergence herbicides are unneeded. Marestail is the one weed in this group that can often be adequately controlled with residual herbicides (assuming an effective burndown). Residual control of marestail is essential in RoundupReady and nonGMO soybeans, since there are no postemergence options. And also in Xtend soybeans, if the goal is to use dicamba only in burndown programs, avoiding postemergence use. Off-target movement of dicamba, which was widespread in 2017, has much greater potential to cause problems from postemergence application. University weed scientists are fairly united in their opinion that dicamba use would be better restricted to early season, in burndown programs. The other three weeds mentioned here do not necessarily require postemergence dicamba use, since glyphosate/PPO inhibitor combinations can still be effective. However, failure to use an appropriate residual program in Xtend soybeans can result in mid-season marestail escapes, driving a need for postemergence dicamba.

    We have been making the same residual herbicide herbicide recommendations on marestail for several years, and they are based on the following:

    - the ALS resistance means that the chlorimuron, cloransulam, or imazethapyr that is in many residual premixes provides no residual control

    - the only other active ingredients with residual activity are metribuzin, flumioxazin, and sulfentrazone. Higher rates of Sharpen provide some residual. Dicamba and the 1 oz rate of Sharpen provide negligiable residual which is short-lived.

    - the residual activity from any one of these actives varies from year to year and field to field in our research, resulting in inconsistent control. Control with metribuzin has been rate dependent – increasing with rate from 6 to 12 oz of 75 DF.

    • mixtures of two active ingredients provide more consistently effective control, which is the basis of our recommendation to add 6 to 8 oz of metribuzin 75 DF to products that contain flumioxazin or sulfentrazone. It’s also possible to improve control by using 1.5 to 2 oz of Sharpen with metribuzin, but this requires a 15 to 30 day wait to plant.

    Based on this we can put premixes roughly into one of three categories with regard to residual marestail control: most consistently effective (two actives), variable (one active); and no control. This information can also be gleaned from the marestail ratings in the herbicide efficacy tables in the “2018 Weed Control Guide for Ohio, Indiana, and Illinois”. We can’t keep track of all generic equivalents so there are more trade names available for certain premixes than are listed here. Keep in kind that just because a premix contains the right components for maximum marestail residual does not mean it has the right ones for ragweeds.

    Most consistent residual (two actives), higher labeled rates required in some cases

    Panther Pro, Trivence, Authority MTZ, Ransom

    Variable residual (one active)

    Afforia, Authority First/Sonic, Authority MAXX/XL, Authority Assist, Zone, Broadaxe XC, Envive/Enlite, Fierce, Fierce XLT, Latir/Militia, Surveil, Valor XLT

    Variable residual sub-category - more metribuzin needed depending upon product rate

    Cloak DF, Canopy Blend, Matador, Intimidator, Boundary/Ledger/Tailwind

    No or little residual

    Anthem MAXX, Prefix/Vise/Statement, Pummel, Torment, Warrant Ultra, Zidua PRO

    Deficiences in residual on marestail for individual premixes can be compensated for by the strategies outlined above. For example, Zidua PRO has almost no residual activity on marestail, but is often applied with metribuzin. In this and any other case where metribuzin is carrying the full load, rates of 10 to 12 oz 75DF will be more effective than 6 to 8 oz. Some products contain metribuzin, but require additional amounts to reach a total metribuzin rate that has a chance to provide enough residual. Example – 4 oz of Canopy Blend contains the equivalent of 2.7 oz of metribuzin 75 DF, so our recommendation would to add about another 4 to 8 oz of metribuzin 75DF, depending upon soil type.

    In other news – we still have OSU Weed Science folders available, and also and the cloth posters showing waterhemp and Palmer amaranth. We prefer the posters go in high visibility areas, and they can be mailed. Contact Mark Loux for more information –

  3. Bin run seed – some lessons from the past

    Author(s): Anne Dorrance

    With lower prices and higher input costs in todays soybean farming operations, some farmers are looking where to shave a few dollars off their costs of farming. Based on the calls directly from farmers on which seed treatments to use – it is not too hard to figure out where some of those savings might be coming from. This used to be general practice but there are ways to do this to be sure it really is saving farmer’s money.

    1. Make absolutely sure that this seed is a candidate to use again. The harsh reality of the new generation of technologies that go into the new soybean varieties is that it probably takes the total profit of the US soybean crop to go from discovery, development, US & European government approvals, and producing that seed. Companies are forced to protect that investment and in reality – part of how we have raised the state yield average from 30 bu/A to 52 bu/A is because of these improved varieties.
    2. Make sure your seed is healthy. Germination tests are very important, it was a tough fall and as you look at that seed there may be a lot of discolored, moldy seed from Phomopsis or Cercospora. There may also be splits – as some seed was harvested last fall well below 13%. Some of our seed was at 9% before we could get to the fields. So this will reduce your viability. Ohio Seed Improvement Association (614- 889-1136) does have the appropriate seed germinators to run these tests for a fee. Also, for testing at home, use one of your baking dishes, line it with paper towels, and run water over it, drain the excess water, then scatter 100 or more seeds over the bottom of the dish. Cover again with more paper towels, add just enough water to moisten that top layer. Leave on the counter or in a warm room for 5 to 6 days, keeping the seed moist but not swimming in water, and check the germ. If it is not over 85%, it is probably best to buy new seed. Note use several pans from seed collected from the different fields.
    3. Don’t repeat problems, diseases from last fall. Three pathogens were in different areas of the state that can be carried with seed.
      1. Sclerotinia stem rot or white mold. This popped up in several areas last year. The sclerotia, those hard black irregular shaped structures, can be harvested with the seed and then if not properly cleaned can end up back in the soil in the seed furrow. Also, some seed will have mycelium of the fungus, that white fluff that you see on the stems. This can also contribute to poor stands in the spring.

      1. Phomopsis seed decay. White, chalky, moldy seed was quite common this year, especially in areas of the state that had a lot of rain during pod fill. This disease will directly impact seed viability. But some seed will carry the fungus on the outer layers, but it won’t have reached the internal layers. When a fungicide that targets this fungus is used, germination of the seed lot can be improved. Again, if overall germination is below 85% and the seed is really moldy, best to get new seed.

      1. Purple seed stain. Especially in the southern counties, Cercospora blight, in addition to frogeye leaf spot made a late season appearance. First, a request, if you do have seed with symptoms of purple seed stain, there is a study, funded by the soybean check-off, in progress which is looking at all of the strains that cause this disease across the U.S. It helps us to have samples in this study. Please send these to me @ 1680 Madison Ave., Wooster, OH 44691. We will verify that they are the right fungus and ship them to our colleague.

      1. What seed treatments will work to protect germ and limit spread of these pathogens? Most of the data available today is based on Phomopsis, and there are a number of active ingredients that can protect seed – when the seed is contaminated with mycelium but not the germ, and when an infected seed is placed right next to a healthy seed in the seed furrow. Look for seed treatments that have one of the following active ingredients: fludioxonil, fluxapyroxad, ipconazole, PCNB, penflufen, prothioconazole, pyraclostrobin, or sedexane. Data is from the combined studies of members of the NCERA-137 Soybean Pathologists from the Land Grant Colleges in the soybean producing states.
      2. The most important advise ROTATE FIELDS. In addition to the ability to survive or contaminate seed, all of these pathogens have survival structures in the soil or on soybean residu To get off on the right foot for 2018 – plant the fields that has problems, lower yields, plants with symptoms of early dying from a plethora of problems, or moldy seed to corn preferably. Or if you must plant soybeans, work with your seed dealer to get the best disease resistance package in that field. We can solve all of these problems by planting varieties with better disease resistance packages targeted for our areas.
  4. Crop Production Costs – Do you know yours? A quick look at the 2016 Ohio Farm Business Analysis

    Which number is closest to your total direct and overhead cost of production per bushel of corn: $3.08, $4.17, or $6.21? Do you know? Forty-two farms completed their 2016 farm business and crop enterprise analysis in 2017. The four lowest cost producers averaged $3.08 per bushel, the median COP was $4.17, and the four highest cost producers averaged $6.21 per bushel.

    Only the high 20% of these corn enterprises generated a positive net return for corn. For the other 80%, the personalized benchmark reports they receive helped them identify strengths and areas of opportunity in each crop enterprise.

    The highest cost producers will know if their costs were high compared to previous years due to weather or other yield-depressing event or if these numbers are “normal” and are waving a big red flag. Combining the real-numbers information from enterprise and benchmark reports with production information gives each farm manager powerful information to make positive changes.

    The 2016 Ohio Farm Business Analysis Crop Summary with Benchmark Reports is now available to download at Forty-two farms with 27,733 crop acres completed both whole farm and enterprise analysis for their 2016 business year. Farm size ranged from 40 to more than 1,900 acres.

    The report includes enterprise summaries and benchmark reports for corn, corn silage, soybeans, wheat, alfalfa and mixed hay. Any farm can use this information to supplement their decision-making.

    All crop, livestock and dairy farms are encouraged to do farm business analysis for their farm. Thanks to a three-year grant from USDA, Ohio has expanded capacity to do farm business analysis work with four additional Farm Business Analysis Technicians working in Ohio. Each farm receives their farm’s analysis as soon as it is completed. All analyses will be completed by the end of May with benchmark reports and summaries available this summer.

    Now is the perfect time to start farm business analysis. For more information, contact a Technician near you:

    Defiance County 419.782.4771 Clint Schroeder

    Licking County 740.670.5315 Dave Grum

    Mahoning County 330.533.5538 Cristina Benton

    Miami County 937.440.3945 Sharon Harris

    Pickaway County 740.474.7534 Trish Levering

    Thanks to the USDA-NIFA Farm Business Analysis grant, the cost for a farm to complete an analysis for the 2017 business year is $100. To learn more about farm business analysis, contact Dianne Shoemaker or Haley Shoemaker at 330-533-5538 or email at or See past farm business summaries at

  5. Topdressing Wheat with Liquid Swine Manure

    Author(s): Glen Arnold, CCA

    Despite the rainfall expected across Ohio this week, wheat fields will eventually firm up and the topdressing of nitrogen fertilizer will commence. There is usually a window of time, typically around the last week of March or the first week of April, when wheat fields are firm enough to support manure application equipment. By this date, wheat fields have broken dormancy and are actively pulling moisture and nutrients from the soil.

    The key to applying the correct amount of manure to fertilize wheat is to know the manure’s nitrogen content. Most manure tests reveal total nitrogen, ammonia nitrogen and organic nitrogen amounts. The ammonia nitrogen portion is readily available for plant growth. The organic nitrogen portion takes considerably longer to mineralize and generally will not be available when wheat uptakes the majority of its nitrogen in the months of April and May.

    Some manure tests also list a “first year available” nitrogen amount. This number is basically the ammonia nitrogen portion of the manure plus about half the organic nitrogen portion. Again, for the purpose of fertilizing wheat, the organic portion of the nitrogen should not be considered available in time to impact yields.

    Most deep-pit swine finishing manure will contain between 32 and 45 pounds of ammonia nitrogen per 1,000 gallons. Finishing buildings with bowl waters and other water conservation systems can result in nitrogen amounts towards the upper end of this range. Finishing buildings with fixed nipple waters and surface water occasionally entering the pit can result in nitrogen amounts towards the lower end of this range.

    To capture the most nutrients from manure farmers should consider incorporation. Incorporation can result in less nitrogen loss and can especially reduce the loss of dissolved phosphorus. Unfortunately, there are very few toolbars designed to incorporate manure into wheat.

    Three years of on-farm wheat top-dress results are summarized in Table 1. Each field trial was replicated four times. In each plot, the manure ammonia nitrogen application rate was similar to the nitrogen amount in the urea fertilizer; typically about 105 pounds per acre. The manure was applied using a 4,800 gallon tanker with a Peecon toolbar 13.5 feet in width. This toolbar cut the soil surface with a straight coulter and a boot applied the manure over the soil opening. Urea was applied using a standard fertilizer buggy.

    Table 1. On-farm Swine Fishing Manure Topdressing of Wheat Results (bu/ac)


    Swine manure (surface applied)*

    Swine manure (incorporated)


    Date of nutrient application





    April 7th





    April 3rd





    March 28th

    *Incorporation was performed with a modified Peecan toolbar attached to a 4,800 gallon tanker

    In addition to the Peecon toolbar, OSU Extension as also conducted manure research on wheat using the both the Veenhuizen (Grassland applicator) toolbar and Aerway toolbar. All toolbars cutting through the soil surface cause some damage to the growing wheat, but side-by-side yield comparisons with conventional surface applied fertilizer have rarely shown any difference in yields.

    Some Ohio commercial dragline operators are routinely applying livestock manure to wheat each spring. This practice is gaining acceptance as it’s faster and more efficient than manure application with a tanker. The risk of soil compaction is also reduced.

    Dairy manure has been utilized with on-farm research plots when topdressing wheat. Dairy manure contains far less ammonia nitrogen per 1,000 gallons than swine finishing manure and does not consistently produce wheat yields similar to commercial fertilizer. Research on dairy manure as a top-dress to wheat by adding 28%UAN to the dairy manure to increase its fertilizer value has produced wheat yields similar to commercial nitrogen.

    When applying livestock manure to wheat it’s recommended to follow the NRCS #590 Waste Utilization Standard to minimize potential environmental impacts. These standards include a 35 foot wide vegetative strip setback from ditches and streams. Applicators in the Western Lake Erie Basin also need to look at the weather forecast to be certain there is not greater than a 50 percent chance of a half-inch of rain in the 24 hours following manure application. Print this forecast out so you have proof in the event of a surprise downpour.

    Additional on-farm manure top-dress of wheat plot results can be obtained by clicking on the on-farm research link on the OSU Extension Agronomics Crops team website at

    OSU Extension YouTube videos of manure to wheat and corn can be found here

  6. Conservation Tillage Conference: New Topics for Changing Ag

    Author(s): Mark Badertscher

    So what is the relationship between healthy soils and healthy water? How can you manage inputs and planting date for high economic corn yields? Which soils should respond to sulfur applications? What are some opportunities and considerations with subsurface placement of nutrients? How can you build soil health and organic matter with cover crops and no-till? How can you use economics in the choice between growing corn and soybeans? What will the revised P index look like? How can you get started in honey bees, barley, or hops production? What are some methods to manage invasive plants around the farm?

    These are all questions you might have asked yourself, but have struggled to find an answer. This year’s Conservation Tillage Conference (CTC) has the answers to these questions and many more. The McIntosh Center at Ohio Northern University will once again be the location were about 60 presenters, several agribusiness exhibitors, and approximately 900 participants will come together March 6th and 7th in Ada, Ohio. Attend this year’s conference to add value to your operation by learning new ideas and technologies to expand your agronomic crops knowledge.

    A general session with well-known author David Montgomery from the University of Washington discussing “From Dirt to Regenerating our Soils” will officially open this year’s conference. Corn University, Nutrient Management, Precision Ag & Digital Technologies, Healthy Soils for Healthy Water, Regenerative Ag, and Healthy Foods from Healthy Soils are the sessions that make up day one.

    On the second day, conference participants will be able to choose from Soybean School, Water Quality Research and BMPs, Alternative Crops, Pest Management of the Atypical Pests: Slugs, voles and more, Healthy Soils for Healthy Waters Precision Nutrient Management, and Healthy Water. In addition, there will be an EPA required dicamba training on both days of this year’s Conservation Tillage Conference provided for pesticide applicators in attendance. To register for one of these Monsanto-provided dicamba application requirements training events, go to:

    Find out what experts from OSU Extension, OARDC, USDA, and SWCD are learning from the latest research about the timely topics that affect today’s farmers, crop consultants, and agribusiness professionals who are out in the field working together to produce crops in an efficient and environmentally responsible manner. Certified Crop Adviser (CCA) and Certified Livestock Manager (CLM) credits will be available to those who attend. Visit and make plans to participate in this year’s Conservation Tillage Conference by February 24 to take advantage of early registration rates.

  7. Nutrient Management and Cover Crops Meeting

    Author(s): Jeff Stachler

    Applying crop nutrients when they are not needed is costly, especially in the current farm economy and harmful to the environment. Conversely, not applying enough fertilizer will cause a reduction in crop yield causing a decrease in profitability.

    Cover crops are important to soil health, but how do you make them work? There are many options, what is the best option for your operation? Is soil health important? These questions along with nutrient management will be addressed at the upcoming meeting entitled: “Improving Your Bottom Line With Nutrients and Cover Crops”.

    The meeting will be held March 13, 2018 from 9:15 AM to 3:40 PM at the Eagles in Wapakoneta (25 E. Auglaize St.).

    Topics that will be discussed include: Basics of Cover Crops, Cover Crops for Forages, Making Cover Crops Work, Nitrogen and Gypsum Research Results, Nitrogen and Phosphorus Management and Management of Micronutrients. Speakers include: Alan Sundermeier, Allen Gahler, Mike Dailey, Joe Nester, Greg LaBarge, and Harold Watters.

    There is no cost to the program because it is being sponsored by the Auglaize County Farm Bureau and Ohio Soybean Council. Please register by March 7, 2018 by calling 419-739-6580 or sending an e-mail to

    Get yourself signed up for this important meeting. Have a great day!

  8. Crawford Agronomy Night March 1st

    The Crawford County Agronomy night with pesticide and fertilizer recertification will be held on March 1st, at the Wayside Chapel Community Center 2341 Kerstetter Rd Bucyrus Ohio 44820. The program will start at 3:30pm and run until 9:00pm. We will have special guest speakers, Dr. Pierce Paul covering corn and wheat diseases; Tunsisa Hurisso with the OSU Soils lab covering Soil carbon, microbes, and nitrogen; Poet will also be providing a corn market update; Other topics coved by local educators: Weed management programs for your farm, Managing herbicide drift and carry over, and Toxic plants and Livestock. All pesticide categories can be covered if needed. Attendees who need credits can attend for $50, you may also attend for education only for $20 Supper is included. For more information click on the picture below, visit or call 419-562-8731.

About the C.O.R.N. Newsletter

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.


Debbie Brown, CCA (Shelby County)
Elizabeth Hawkins (Field Specialist, Agronomic Systems)
Glen Arnold, CCA (Field Specialist, Manure Nutrient Management )
Greg LaBarge, CPAg/CCA (Field Specialist, Agronomic Systems)
Jason Hartschuh, CCA (Crawford County)
Les Ober, CCA (Geauga County)
Mark Badertscher (Hardin County)
Mark Loux (State Specialist, Weed Science)
Rory Lewandowski, CCA (Wayne County)


The information presented here, along with any trade names used, is supplied with the understanding that no discrimination is intended and no endorsement is made by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions.

CFAES provides research and related educational programs to clientele on a nondiscriminatory basis. For more information, visit For an accessible format of this publication, visit