Corn Newsletter : 2020-06

  1. Wet Weather for the Rest of March

    Author(s): Jim Noel

    Current Conditions...Soil moisture conditions remain wet due to last years very wet conditions along with an overall damp winter. Current soil moisture conditions can be found at the NOAA/NWS website:

    What it shows is Ohio is ranked anywhere from the top 5-25% of wettest years on record for soil wetness depending on where you are in Ohio. This is slightly drier than at the same time last year but bottom line it is still wet. The last 30-days of rainfall is generally between 90-140% of normal across Ohio. The extreme northwest corner of Ohio has been running at about 80% of normal. About 75% of the state has been running wetter than normal the last 30 days with about 25% a little drier than normal. You can get all the latest information on precipitation at 4 km resolution at: This data is quality controlled by humans at the river forecast centers like OHRFC.

    Future Conditions...The outlook for the rest of March calls for slightly above normal temperatures with much above normal rainfall. Temperatures for the week of March 16 will be above normal but with big temperature swings. Temperatures will likely run a little colder than normal the week of March 23.

    Rainfall will average 1.75 to 3.50 inches for the remainder of March, see NOAA/NWS/OHRFC attached image. Normal for that period is 1.5 to 2.0 inches.

    For April expect above normal temperatures and above normal rainfall.

    For May expect above normal temperatures with a gradual turn from wetter than normal to normal rainfall.

    Frost/Freeze Outlook...Indications are even with somewhat above normal temperatures expected overall this spring, there is enough swings in the pattern to expect about a normal last frost/freeze across the state. 

    Soil Temp Outlook...Soil Temperatures are running mainly in the 30s north of I-70 and in the 40s to the south of I-70. Temperatures due to the winter have generally been above normal. However, we expect them to trend close to normal due to the high amount of water in the soils. Therefore, even if air temperatures run somewhat above normal, evaporation off the wet soils will keep ground temperatures close to normal as we go into the growing season.

    For summer, indications still remain a gradual turn from wetter to drier with warmer than normal conditions.

    Climate Outlook Websites...You can see all the latest climate outlooks at the NOAA Climate Prediction Center: For the latest Water Resources Outlooks for soil conditions, floods etc, you can monitor the NWS Ohio River Forecast Center Page at:

  2. Winter Wheat Stand Evaluation

    Author(s): Laura Lindsey

    Between planting in the fall and Feekes 4 growth stage (beginning of erect growth) in the spring, winter wheat is vulnerable to environmental stress such as saturated soils and freeze-thaw cycles that cause soil heaving. All of which may lead to substantial stand reduction, and consequently, low grain yield. However, a stand that looks thin in the spring does not always correspond to lower grain yield. Rather than relying on a visual assessment, we suggest counting the number of wheat stems or using the mobile phone app (Canopeo) to estimate wheat grain yield.







    Wheat stem count method. Wheat stems (main stem plus tillers) should be counted at Feekes 5 growth stage (leaf sheaths strongly erect) from one linear foot of row from several areas within a field.










    Canopeo mobile phone app method. Canopy cover should be measured at Feekes 5 growth stage using the mobile phone application, Canopeo ( After accessing the app, hold your cell phone parallel to the ground to capture three rows of wheat in the image and take a picture. The app will convert the picture to black and white and quantify (as a percentage) the amount of green pixels in the image. For example, the screen shot here shows 44.86% canopy cover. (Keep in mind, this app will quantify anything green in the image. So, if you have a weedy field, the weeds will also be quantified in the canopy cover estimate.)

    After counting the number of wheat stems or measuring canopy cover using the Canopeo app, the table below can be used to estimate wheat grain yield. For example, if an average of 51 stems is counted from one foot length of row, the predicted grain yield would be 100 bu/acre. Similarly, if the average canopy cover was 35%, the predicted grain yield would be 100 bu/acre.

    Grain Yield (bu/acre)

    Stem Count (number/foot of row)

    Canopy Cover (%)































    This table was generated using data from two years and two locations (four different environments). During these two years, wheat grain yield was relatively high. We do not have data for wheat grain yield <85 bu/acre. However, we are continuing this work and hope to capture a wider range of yields to expand this table.

    For more information, please see:

  3. Phosphorus Placement Effects on Yield and Water Quality in a Corn-Soybean Rotation

    Phosphorus placement has been discussed as a 4R Best Management Practice that results in lower nutrient losses than when P is surface applied and left on the surface. The concept is that by mixing granular fertilizer with the soil, we expose the nutrient to more soil surface area for attachment. A replicated trial was established at the Northwest Agricultural Research Station-OARDC located near Custer, OH to measure water quality and crop yield with four fertilizer placement options.

    Four phosphorus fertilizer treatments are being used:

    1. Surf - Broadcast surface application in fall
    2. 2”x2” - 2 by 2 placement at spring planting
    3. Deep - Deep banding using strip till unit in fall
    4. Incorp - Surface application with disk incorporation in fall

    Corn and soybean are planted on 50% of the plot each year. The rate of phosphorus applied for fall treatments is 128 pounds P2O5 applied after the soybean crop and 64 pounds P2O5 in the 2 by 2 placement to both corn and soybean. Fertilizer treatment were applied in fall of 2018/spring 2019.  The STP level is 40 PPM Mehlich III. Water samples are collected using ISCO samplers with only water from subsurface drainage collected.

    Preliminary water quality results are presented below for the period January to September 2019. The surface placement plot yielded the highest concentration of DRP and loading in the collected tile water. All treatments that placed P2O5 in contact with the soil resulted in lower DRP concentrations and loading.

    Figure 1. DRP Concentration and Load from phosphorus placement measured through subsurface drainage.







    Corn and soybean yield average 144.4 and 47.7 bushels per acre respectively with no significant response to fertilizer placement. Yield response data is shown in Table 1 below.

    Table 1. Corn and Soybean yield from phosphorus placement in 2019.


    Soybean (bu/A)

    Corn (bu/A)













    LSD (0.1)









  4. Topdressing Wheat with Liquid Swine Manure

    Author(s): Glen Arnold, CCA

    Wheat fields will begin to firm up in Ohio and the topdressing with nitrogen fertilizer will soon start. 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.

    Most deep-pit swine finishing manure will contain between 30 and 40 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.

    The typical application rate for liquid swine finishing manure on wheat is 4,000 gallons per acre. Wheat removes 0.49 pounds of P2O5 per bushel harvested. When also harvesting the wheat straw, a ton of wheat straw contains between three and four pounds of P2O5. So, a 100 bushel wheat crop with one ton of straw also removed would withdraw about 52 pounds of P2O5 per acre. This is likely about the same amount of P2O5 as 4,000 gallons of swine manure would contain but review your manure test to make this determination.

    If you are participating in the H2Ohio program, manure must be incorporated if being applied to wheat in the spring. The grassland application toolbar (also known as the Veenhuis toolbar, see header above and picture below) slices furrows in wheat, forage, and pasture fields at a spacing of about 7.5 inches and places manure over the furrows. I believe the Ohio Department of Agriculture will approve this as incorporation but check with your local Soil and Water Conservation District in advance to be sure. OSU Extension has conducted manure research using the grassland applicator in replicated plots and got yields slightly better than top-dressed urea.

    A farmer near New Washington, Ohio has a refurbished 22-foot wide grassland applicator with a hitch designed to be pulled behind a manure tanker. He is willing to rent the toolbar on a per acre basis if anyone wants to give the technology a try. Aerway and Gentill toolbars will not currently qualify in the H2Ohio program as manure incorporation toolbars.

    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 if surface applying. Print this forecast so you have proof in the event of a surprise rain downpour.

  5. "What's your number?" The SCN Coalition is still in progress

    Author(s): Anne Dorrance

    There is a lot of information already out and if you haven’t take the time, check out  the website, for training and infographics about soybean cyst nematode, you can bookmark this for as you prepare your fields– while on autosteer.  Only on autosteer.  Our Ohio site, with updated information is also ready  Take your time to see where this pest has been detected, where some of the hot spots are and what we need to be aware of for management.  This pest can not be eradicated or removed from a field once it is there, but there is no reason why it should take a lot of our soybean yield, we just need to manage it and that starts with knowing your number.

    The first surveys for SCN, early 1990’s, found it sporadically in the state but some populations were very high.  In a survey of fields in southern Ohio during the late 2000s, high populations of SCN were found in fields where yields were consistently low.  One of the more recent check-off funded projects, identified that more fields than 20 years ago has SCN.  Among the 143 fields sampled at a depth of 6 to 8 inches in 51 counties in Ohio, SCN was detected in 81% of the fields and only 6 of the 147 were above the yield damaging levels. 

    In the current survey, SCN is now at economically damaging levels in approximately 15% of the fields sampled in the current survey.  This is a concern. 

    In addition to more fields planted more frequently to soybean, there are other potential reasons for this increase.  SCN has been managed very well for the last 20 years by the deployment of soybean varieties with the PI 88788 source of resistance.  However, in Ohio as well as many areas of the Midwest, certain fields have populations that are adapting to this resistance.  This resistance is a “slow shift” where the SCN reproduction on the resistant line is greater than 10% compared to a susceptible control cultivar.  In fungi, where resistance has developed towards some fungicide this measurement would be 100%, one mutation and the fungus is good to go.  In SCN there are several loci and as we now know many copies of the genes, so it is taking longer to adapt but also it is a slow shift where the SCN reproduction of some populations in Ohio and other areas of the Midwest are in the 15, 20, and 30%.  Ultimately this means that the resistance can still be used.  But for how long, and what fields are we expecting yield loss even with varieties developed from the PI 88788 source of resistance.

    In the current survey, we are picking up populations that are adapting to the PI 88788 and Peking sources of resistance.

    We are still accepting samples, but we will not process them until later this spring. If you collect samples just hold them in a cool spot in the barn or cellar, out of the light and heat.  The survey will end this summer, so while we are practicing social distancing and you need to get out and get some fresh air, take your soil sampler and hit some of those low spots in the fields.

  6. eFields 2019 Results Webinar - March 25, 9 AM

    Have you been enjoying the 2019 eFields Report and are excited to learn more? The Ohio State Digital Ag team is hosting an eFields Results webinar on March 25th, 9 – 10 AM. Join us to learn more about the eFields program and results we are seeing across the state. The webinar will feature presentations highlighting popular trials including seeding rate, nutrient management, and crop management. We would also like to hear from you about what topics you are interested in seeing in eFields in the future.

    There is no cost to attend; for more information or to register visit:

  7. H2Ohio Signup to be Extended

    Author(s): Glen Arnold, CCA

    The deadline to enter into a contract with the H2Ohio program for farmers in the 14-county, Maumee River watershed is being extended. The original deadline was March 31st but due to COVID-19, more farmers and Soil and Water Conservation District personnel are conducting information exchanges through phone calls and e-mails.

    The H2Ohio deadline is expected to be extended to June 2nd,tentatively. Contact your local Soil and Water Conservation District for more details.

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.


Allen Gahler (Sandusky County)
Andrew Holden (Ashtabula County)
Andy Michel (State Specialist, Entomology)
Ann Chanon (Lorain County)
Anne Dorrance (State Specialist, Soybean Diseases)
Chris Zoller (Tuscarawas County)
Clifton Martin, CCA (Muskingum County)
Elizabeth Hawkins (Field Specialist, Agronomic Systems)
Eric Richer, CCA (Fulton County)
Garth Ruff (Henry County)
Glen Arnold, CCA (Field Specialist, Manure Nutrient Management )
Greg LaBarge, CPAg/CCA (Field Specialist, Agronomic Systems)
Harold Watters, CPAg/CCA (Field Specialist, Agronomic Systems)
Jeff Stachler (Auglaize County)
Jim Noel (National Weather Service)
Les Ober, CCA (Geauga County)
Mark Badertscher (Hardin County)
Mary Griffith (Madison County)
Mike Estadt (Pickaway County)
Mike Gastier, CCA (Huron County)
Rory Lewandowski, CCA (Wayne County)
Sam Custer (Darke County)
Sarah Noggle (Paulding County)
Steve Culman (State Specialist, Soil Fertility)
Ted Wiseman (Perry County)
Will Hamman (Pike 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