C.O.R.N. Newsletter: 2023-22
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Nutrient Value of Wheat Straw
Before removing straw from the field, it is important for farmers to understand the nutrient value. Though we have seen some softening of the 2022 fertilizer prices, P and K fertilizer prices remain higher than normal. The nutrient value of wheat straw is influenced by several factors including weather, variety, and cultural practices. Thus, the most accurate values require sending a sample of the straw to an analytical laboratory. However, “book values” can be used to estimate the nutrient value of wheat straw. In previous newsletters, we reported that typically a ton of wheat straw contains approximately 11 pounds of N, 3.7 pounds of P2O5, and 29 pounds of K2O. According to June 2023 fertilizer prices (Source: DTN Fertilizer Price Index: Ohio) and nutrient removal “book values”, one ton of wheat straw would remove N, P, K valuing approximately $25.13 ($16.55 of P2O5 & K2O).
Table 1. What is the value of your straw? P2O5, and K2O removed in straw, June 2023 fertilizer prices, and total value of P & K nutrients within wheat straw.
P2O5 K2O Removed in Straw 3.7 lb/ton 29 lb/ton June 2023 Price $.79/lb P2O5 $0.47/lb K2O Value $2.92/ton $13.63/ton Total = $16.55/ton Although N adds value, we do not give it an economic value in the form of fertilizer (as seen in Table 1). Within straw, N is in an organic form and will not immediately be available for plant uptake. The organic-N will need to be converted by microorganisms to ammonium-N (an inorganic form) before it is available for plant uptake – a process called mineralization. The rate of which mineralization occurs depends on the amount of carbon (C) and N in the straw (C:N ratio). The USDA reports a C:N ratio of 80:1 for wheat straw which means there are 80 units of C for every unit of N. Mineralization rapidly occurs when the C:N ratio is ≤ 20:1. At a C:N ratio of 80:1, mineralization will be much slower. (For comparison, corn stover is reported to have a C:N ratio of 57:1.) Rate of mineralization is also influenced by soil moisture and temperature. Since mineralization is a microbial-driven process, mineralization will be slowed (halted) in the winter when temperatures are cold. Thus, no N credit (i.e., value) is given for wheat straw since it is not known when the N will mineralize and become available to the following crop.
In addition to N, removal of straw does lower soil K levels. If straw is removed after heavy rainfall, some of the K may have leached out of the straw, lowering the nutrient value. However, a soil test should be done to accurately estimate nutrient availability for future crops. Besides providing nutrients, straw has value as organic matter, but it is difficult to determine the dollar value for it.
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Smoke from Wildfires Affecting Ohio Agriculture? Or Some Other Stressors?
Wildland fires in Canada this year have so far burned over 20 million acres with approximately 4 million of those acres in Quebec. In spite of these fires being hundreds of miles away from us, smoke generated has been driven by northern winds impacting the northeastern and midwestern US. There has been some growing concern about the impact this smoke will have on agriculture in Ohio. Of particular concern are toxins in the smoke.
Wildland fire smoke is made up of small particles, gases, and water vapor. Water vapor makes up the majority of smoke. The remainder includes carbon monoxide, carbon dioxide, nitrogen oxide, and small amounts of other compounds. Among the particulates in smoke are many compounds which do not turn into a gas during the fire, such as calcium, sodium, and magnesium. As particulates, these substances can be carried down-wind and have a minor fertilization effect. Another compound produced by wildland fire is dioxin. Dioxins are compounds produced as byproducts of some processes including smoking cigarettes, paper production, industrial and structural fires, and wildland fires. Dioxins are known to be cancer causing. The quantity of dioxin produced from wildland fire is highly variable and will depend largely on the population of fungi in the forest.
While the smoke from Canada’s fires is reducing air quality and visibility across the Midwest, it is highly unlikely that these fires are going to have any kind of impact on Ohio agriculture. Ohio is a significant distance from the fire locations, and the smoke has dispersed hundreds of miles in all directions, thereby reducing the quantity of smoke and its various components. Combined with the low quantity of toxins in wildland fire smoke to begin with, we can see that there is very little to worry about in terms the impacts of this smoke on crops or livestock.
Although wildfires are not likely to be the cause, there are several soybean issues popping up in areas of the state:
1. Poor nodulation. Yellow soybeans that can also be somewhat stunted are often indicative of poor nodulation (Figure 1). Nodules are small knots found on roots, often near the top of the root system. Nodules are the result of a symbiotic relationship between soybean and bacteria (Bradyrhizobium japonicum). These bacteria convert nitrogen into a form that is usable by the soybean plant. Nodulation and nitrogen fixation by Bradyrhizobium japonicum is reduced in wet soils. Plants should be able to recuperate nodule function when normal (aerobic) conditions are restored. To determine if a nodule is actively fixing nitrogen (i.e., converting nitrogen to a usable form), split the nodule with your fingernail and examine the inside. If the inside of the nodule is pink or red, nitrogen is being fixed.
2. Overall slow growth and poor root development. While cooler weather in April and May limited crop stress symptomology to some degree, dry conditions can lead to slow root growth and poor nodulation in soybeans. Root exploration is key to moisture acquisition and nutrient uptake. Dry conditions early (paired with cooler temperatures) may have slowed initial root development and formation. Planting deeper (as may have been done to reach moisture depending on location and planting date) could also affect root development by slowing the accumulation of early GDDs; in corn, soil accumulated GDDs affects early-season growth more than air temperature GDDs.
In many parts of the state the dry conditions were replaced within the span of a few days with the other extreme in the form of waterlogged soils and excess water conditions. Very few studies have been published examining subsequent stresses of drought followed by flood, but one article from cabbage suggests drought followed by flooding was worse for crops than drought alone. In corn, roots will form arenchyma in central cortical cells to cope with waterlogging. Soybean aerenchyma formation, though, requires creation of a new cell layer near the outside of the roots that contain the internal air pockets. This will typically occur near the water line for flooded plants (Figure 2).
Another typical symptom is that when stressed soybeans are removed from the soil the outer cortical layer may easily slough off when handled (see this article from 2021 to help discern flood damage and root rots). The characteristic “rat tail” cortex remaining is a key indicator that flood damage occurred. The rapid change from drought to waterlogged conditions paired with below average nodulation is a likely contributor toward our yellow soybeans this year.
3. Potassium deficiency. Potassium deficiency may be observed when soil test K levels are low or could be induced by dry weather (Figure 3). Yes, it’s strange to discuss both waterlogging and drought conditions in the same article, but various areas of Ohio have seen one (or both) of these extremes this year. [We reported more on potassium and drought in this article.] Soil testing will help determine if a potassium deficiency is due to low soil test potassium or dry weather. If the cause is dry weather and soil moisture is replenished, these symptoms should go away with time.
4. Diseases. We will expand on diseases in an upcoming article. However, there have been several disease issues noted within Ohio. Many plants have been collected and sent to the Department of Plant Pathology and are currently being tested for pathogens.
Be sure to watch the weather and crops over the next few weeks to see how they respond. Many soybean plants may start to create new roots as the soil dries, and it would be good to check for new nodule formation. If corn height still allows for sidedress N application to supply the remaining seasonal N budget still plan on making that application once soil moisture allows. In recent work from Ohio State, corn still responded positively to N sidedress application after 3 days of flooding or after repeated 3 day floods (3 days flooded, 3 days drying followed by 3 additional days flooded).
References:
Kunert et al. (2016). Drought stress responses in soybean roots and nodules. doi: 10.3389/fpls.2016.01015
Thomas et al. (2005). Aerenchyma formation and recovery from hypoxia of the flooded root system of nodulated soybean. doi: 10.1093/aob/mci272
Barber and Muller (2021). Drought and subsequent soil flooding affect the growth and metabolism of savoy cabbage. doi: 10.3390/ijms222413307
Novais et al. (2023). Elucidating how N management practices and excess water conditions affect corn N uptake and grain yield. https://scisoc.confex.com/scisoc/2022am/meetingapp.cgi/Paper/142573
Swan et al. (1987). Estimating corn growth, yield, and grain moisture from air growing degree days and residue cover. https://doi.org/10.2134/agronj1987.00021962007900010012x
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2023 Northwest Agronomic Field Day
Join us at the 2023 Agronomic Field Day, where we will be discussing new corn and soybean practices you can apply on your farm.
Topics this year include the following:
- Battle for the Belt, Who Will Win? – Corn vs. Soybeans, Osler Ortez and Laura Lindsey
- Managing Slugs with Radish Cover Crops, Rachel Cochran
- Intensive Corn Management, What Pays (and What Doesn’t), Osler Ortez
- What is the Right Nitrogen Rate for Corn Following a Cover Crop?, Nick Eckel
- Effect of Xyway® LFR® Fungicide on Corn, Stephanie Karhoff
Where: Northwest Agricultural Research Station, 4240 Range Line Road, Custar, OH 43511
When: Thursday, August 31
Cost: Free, please RSVP by August 25 to reserve your free lunch courtesy of Ohio Soybean Council
RSVP: https://osu.az1.qualtrics.com/jfe/form/SV_d6eICnD6sqyVvfg
Registration will start at 8:30 a.m. and the program will begin at 9:00 a.m. followed by lunch at 12:00 p.m.
For more information, please contact Nick Eckel (eckel.21@osu.edu), or Matt Davis (davis.1095@osu.edu).
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Manure Science Review Coming Thursday August 3rd
The annual Manure Science Review will be held on Thursday August 3rd in Defiance County from 9:00am to 3:00pm at Innovative Ag, 10366 OH 249, Bryan, Ohio 43506.
Attendees will see and hear about updates on the H2Ohio program from Terry Mescher, H2Ohio Program Director. Mike Cook from Innovative Ag will discuss Ag Poultry Litter: Logistics, Stockpiles and Insect Control. Paige Kelly from the Ohio Poultry Association will talk about Composting Mass Mortality from High Path Avian Influenza Outbreaks. Courtney Krieger, OSU Water Quality Educator, will discuss Composting Bedded Pack Manure research results.
Best Practices for Manure Application will be covered by Frances Springer, ODA Division of Soil & Water Conservation and Glen Arnold will talk about the latest research results on Cultivating in Surface Applied Manure in Corn.
Kurt Kollar of the Ohio EPA has been invited to discuss Spill Response: Best Practices.
The afternoon will be demonstrations of solid and liquid manure applicators, the Cadman Side-dress System, and several companies demonstrating manure application equipment. Optional tours of Vandermade Dairy and EnviroKure are available at the end of the day.
Continuing education credits will be available for Certified Crop Advisors, ODA Certified Livestock Managers, Ohio Fertilizer Recertification, and IN State Chemist. Registration costs are $25 per person until July 25th and $30 per person after that date. For program and registration details, click on the links below or contact Mary Wicks (wicks.14@osu.edu; 330.202.3533).
Program and registration details: click here
Online registration: click here
Sponsor & exhibitor opportunities: click here -
Battle for the Belt: Episode 18
Episode 18 of Battle for the Belt is now available: https://www.youtube.com/watch?v=G1ht5SvBiRg
In Episode 18, we talk with Alex Lindsey, Crop Ecophysiology, about recent weather and the effects of weather on our growing crops. Click here for more information on the effect of the haze on crops.
Battle For the Belt Location Updates
The rain and heat from the end of June and first week of July encouraged growth for both corn and soybeans at the Northwest and Western Research Stations. According to Table 1, Northwest and Western increased in GDDs more in the last week compared to previous week reports earlier in the season. Soil temperatures at 2-inch depth at the Northwest branch reached a high of 92°F, the hottest we have seen all summer. Soybean flowering has occurred throughout planting date one and two at Northwest and Western, marking the beginning of the reproductive stages. Planting date one in corn is getting close to entering reproductive stages at Northwest and Western. More time needed at Wooster since this site has accumulated fewer GDDs.
At the Wooster location there was evidence of possible slug damage on the lower leaves of corn but no significant insect or disease damage at this location. Corn stages for planting date one, two, three, four, and five are V9, V8, V7, V6, and V2, respectively. A few soybeans within the first planting date had flowers but the majority were at V9 stage. The stages for planting date two, three, four, and five are V7, V6, V3, and VC, respectively.
At the Western Research location, planting dates one and two in soybeans reached canopy closure and were at R2 and R1, respectively. The stages for planting date three, four, five, are V8, V5, and V2. The stages for corn at Western were V14, V11, V9, V8, and V5 for planting date one, two, three, four, and five.
At the Northwest Research Station, corn is getting close to tasseling in both planting date one and two.. The stages for planting date one, two, three, four, and five are V14, V13, V11, V8, and V5. The soybeans in planting date one and two have reached R2 and R1 (Figure 1) in the past week and have achieved canopy closure. The stages for planting date three, four, and five are as follows: V10, V8, and V3.
This research project includes five planting date windows, 1) Ultra early = late March to early April; 2) Early = mid to late April; 3) Normal = early to mid-May; 4) Late = late May-first week of June; and 5) Very late = mid to late June. As of today, all locations have all five planting dates planted, emerged, and actively growing (Figure 2).
Keep following the ‘Battle for the Belt’ this growing season to learn more and get further updates! You can find the full video playlist of Battle for the Belt on the Ohio State Agronomy YouTube channel.
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OSU Extension Weather Extremes Committee and the State Climate Office of Ohio to Host Climate Smart: Farming with Weather Extremes
Weather is almost always a challenge for agriculture, and good management strategies for dealing with water, weeds, pests, diseases, and stress are all part of being climate-smart.
The 2023 Climate Smart: Farming with Weather Extremes Conference is set for Thursday, July 20, 2023. The event will take place at Der Dutchman located at 445 S. Jefferson Ave in Plain City, Ohio and will run from 8:30 AM to 3:30 PM with both breakfast and lunch provided. The event has applied for up to 4 CCA credits.
Ohio State and Central State Extension specialists will gather to discuss these important interactions between weather, climate, and agriculture. Speakers include:
- Weather and Climate Update - Aaron B. Wilson
- Federal Climate Smart Funding Landscape and NRCS – Eric Schwab
- Do "Climate Smart" Ag Practices Improve Resilience to Extreme Weather? Evidence From Crop Insurance - Margaret Jodlowski
- Too Much or Too Little? Water Management Challenges for Ohio’s Row Crops - Vinayak Shedekar
- Central State University Extension and Applied Research in Climate Focus Areas - Alcinda "Cindy" Folck and Sakhi Kumaran
- Panel: On Farm Realities and Responses to Extreme Weather (Marc Amante [CSU Specialist – Specialty Growers and Agroforestry], Glen Arnold [OSU Specialist – Manure], Bridget Britton [OSU Specialist - Farm Stress], Elizabeth Hawkins [OSU Specialist - Precision Ag])
- Insect Pests Under a Changing Climate - Maggie Lewis
- How Weather Risk is Presented in the Crop Market - Seungki Lee
The event is free thanks for the following sponsors: Platinum - Ag Resource Management and Carbon by Indigo; Gold - AgCredit, Leist Mercantile, Ohio Corn & Wheat, and Ohio Soybean Council; Silver – AgPro, Merchants National Bank, W.D. Farms LLC, and Vallery & Dorn Insurance; Vendors – ADM and NRCS. Please register by Tuesday July 18, 2023, at go.osu.edu/reg-climate-smart23 or by using the QR code. Please contact Aaron Wilson (wilson.1010@osu.edu; 614-292-7930) for any questions. -
Weather Update: A Slow Drought Improvement
The last two weeks have brought a continued active pattern across Ohio, with numerous showers and storms hitting just about every corner of the state. The most active weather has been focused across the central third of the state, with widespread reports of 2-6” of rain over this period (Figure 1). Lighter amounts have fallen across the far northwest, portions of the northeast, and across southeastern counties. Still, drought area for Ohio is down to 28% as of Thursday July 6, 2023 (US Drought Monitor). Our CFAES Rapid Response Team continues to manage the drought response resource site and encourage readers to continue to submit observations and impacts for your location by visiting https://go.osu.edu/drought_cmor.
Forecast
We will start out under high pressure this week, though a front sagging south into the region could bring a few showers and storms to northern Ohio on Tuesday. The front will stall out over the region for mid-week through the weekend, bringing daily rounds of showers and storms across the entire state. Rain will not occur everywhere, everyday, but locally heavy rain will be possible each day throughout this period. Highs will generally be in the 80s with lows in the 60s all week.
The current Climate Prediction Center’s 8-14 Day Outlook and the 16-Day Rainfall Outlook from NOAA/NWS/Ohio River Forecast Center indicate that probabilities for temperatures and precipitation are leaning above average for the period July 14 – 24, 2023 (Figure 3). Climate averages include a high-temperature range of 84-87°F, a low-temperature range of 63-67°F, and average weekly total precipitation of 0.85-1.0 inch
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Defoliation in Soybean and Corn, and Japanese Beetle Watch
We have been receiving reports of higher-than-typical Japanese beetle activity in horticultural settings (e.g., ornamentals, home gardens) and this may be a warning sign to watch for them in field crops too. Also, there are many weedy fields because of the difficulties with planting and weed management this season. Weedy fields may be more attractive to Japanese beetle and other defoliators because certain weeds are preferred food.
Starting in July and through August, a number of different insect species (such as Japanese beetles, bean leaf beetles, and various caterpillars) can feed on soybean leaves and (for some species) corn. Foliage feeding in corn is almost never economic, though economic damage from silk clipping by Japanese beetles is possible (though rare). Consider a rescue treatment when silks are clipped to less than ½ inch and, fewer than 50% of the plants have been pollinated, and the beetles are still numerous and feeding in the field.
In soybean, while the defoliation damage from various species might look startling, it is rather rare that this reaches economic levels. Soybeans are master compensators. OSU agronomist Dr. Laura Lindsey reports that she has even weed-whacked large portions of soybean foliage for an agronomic study and saw no difference in yield by the end of the season! For defoliating insects in soybean, we usually use an overall defoliation measure as the threshold, regardless of what species is doing the feeding. This helps account for situations where more than one species may be having its bite. Entomologists have recently calculated new thresholds for soybean defoliation based on more modern crop values and input costs. A rescue treatment is advised when defoliation levels reach 30% in pre-bloom stages, 10% during pod development and fill, and 15% at R6 (full seed). After R6, a spray will not pay. These defoliation levels apply to the plant as a whole, not just certain leaves. Damage is often worst at the top of the canopy but on closer examination most of the plant is relatively unharmed. Make your decision based on the average condition of whole plants, not a scan of the top canopy. Also, defoliation tends to be worse on field edges, so make your assessment based on the field as a whole, including interior.
A visual guide to defoliation is useful because it is very easy to over-estimate defoliation in soybean. For more information, visit our Soybean Defoliation scouting card at
https://aginsects.osu.edu/sites/aginsects/files/imce/Soybean%20defoliation%20Final.pdf -
Corn Yield Forecasts for 2023
Corn is progressing nicely across most of the state after well-needed rains (Figure 1). Starting in mid-July 2023, the Yield Forecasting Center plans to provide corn phenology (stages) and forecasts of corn yield potential every three weeks. The center is led by a core team at the University of Nebraska-Lincoln (UNL) that collaborates with agronomists and extension educators from universities throughout the Corn Belt.
Forecasts can help researchers, growers, and industry stakeholders make management, logistics, and marketing decisions during the 2023 crop season. Forecasts cover 40 locations across the Corn Belt, including Western (South Charleston), Northwest (Custar), and Northeast (Wooster site) in Ohio (Figure 2).
The Yield Forecasting Center encompasses the following:
- A network of collaborators providing local management data and verifying forecasted yields.
- Information on dominant soil types in each region.
- Real-time and historical weather data.
- A crop simulation model (UNL Hybrid Maize).
The article below summarizes the methodologies used to forecast corn phenology and yield. It provides guidelines for the interpretation of results:
2023 Corn Yield Forecasts: Approach and Interpretation of ResultsSections in this article outline:
- The approach.
- Accounted and non-accounted factors.
- How Do We Forecast Real-time Corn Yield Potential?
- What to Expect During the Growing Season?
- How to Use These Forecasts to Inform Farm Decisions?
As corn yield and phenology forecasts become available this crop season, short briefs will be released via the OSU C.O.R.N. Newsletter; make sure to subscribe.
Reference:
Grassini, P., Andrade, J., Rizzo, G., Yang, H., Rees, J., Coulter, J., Licht, M., Archontoulis, S., Ciampitti, I., Singh, M., & Ortez, O. (2023). Corn Yield Forecasts: Approach and Interpretation of Results. UNL Nebraska CropWatch. Available from: https://cropwatch.unl.edu/2023/2023-corn-yield-forecasts-approach-and-interpretation-results -
Herbicide Injury
The 2023 growing season has brought a range of stress inducing weather patterns, from drought to waterlogging. Stressful conditions can make crop plants more susceptible to injury from postemergence herbicides. Below are some examples of injury we have seen so far this year.
Yellow flash (glyphosate)
Temporary yellowing of newly emerged soybean leaves due to glyphosate application to glyphosate-resistant beans. More common in:- Conditions conducive to rapid soybean growth (high temperatures and/or humidity)
- High rates/areas of overlap
- Areas with micronutrient deficiency
Injury often appears one to two weeks after application and often disappears by 21 days after the area was treated. There is no evidence of yield loss from this phenomenon.
Glufosinate injury
Injury symptoms where glufosinate was applied to glufosinate-resistant beans:- Chlorosis, or yellowing, and some necrosis
- Often worse when applied in hot, humid conditions
- Injury often short-lived
Leaf malformation
Group 15 herbicides are an important component of late-season waterhemp management in soybean. Use of herbicides like Warrant are known to cause some leaf malformation, which in some instances can look similar to the leaf injury from group 4 herbicides. Some important differences are:- Group 15 injury: heart shaped leaves, shortened midveins, leaf crinkling, irregular symptomology
- Group 4 injury: leaf cupping or strapping, parallel leaf venation, symmetrical symptomology
Leaf burn/speckling
PPO inhibitors like Flexstar are known to cause some injury when applied postemergence.- Leaf speckling or bronzing
- Injury often worse when applied in hot humid conditions
- Plants typically overcome injury within 30 days with no yield loss
Carryover
Ohio typically receives enough rainfall that carryover is not likely if labeled rotational intervals are followed. The droughty conditions this past fall and early spring are causing some concerns over carryover of corn herbicides to soybean and vice versa. Environmental conditions and nutrient deficiencies can cause similar looking issues. Some considerations for diagnosing carryover include applications made the previous season and the herbicides used, injury symptomology, soil type and pH, and environmental conditions.Lots of great resources exist with pictures of the abovementioned injury symptoms associated with different herbicide groups used postemergence:
Yellow Flash in Soybean
Tips for Identifying Postemergence Herbicide Injury Symptoms in Soybean
Herbicide Injury Symptoms on Corn and Soybeans
Identifying Common Herbicide Symptoms in Soybean
Quick Guide to Herbicide Injury on Soybean
Herbicide Injury to Corn -
Lep Monitoring Network Update #10 – Trap Counts for CEW, WBC, and ECB (IA & NY)
The Ohio Lep Network is continuing to monitor moth pests across Ohio. As we enter our tenth week of reporting, we will continue population reports on corn earworm (CEW), Western bean cutworm (WBC), and both variations of European corn borer (ECB - IA & NY).
While monitoring for black cutworm (BCW) and true armyworm (AMW) have both ended for this season, it should be noted that Van Wert County is seeing an increase in both BCW and AMW populations. Across Van Wert County there were an average of 19.5 BCW moths per trap, and 9.5 AMW moths per trap, with there being 12 traps for each in the county.
For more information on these pests and many more, check out our website: https://aginsects.osu.edu
Chasing the Corn Earworm
This is our fourth week monitoring the corn earworm (CEW) pest. Nine counties across Ohio monitored for CEW populations using 13 total bucket traps. The county with the highest average moths was Brown County, which had an average of 24 moths (Figure 1).Corn Earworm (CEW) is a common pest that we see in Ohio and can be seen in corn, tomato, and legume fields. For corn fields, CEW is typically more of a pest for sweet corn compared to field corn. CEW moths are most attracted to fields in the early green silk stage, and lay their eggs, which upon hatching cause ear-feeding damage, attract birds, and invite the possibility of mold. Most CEW damage is seen near the tip of the corn. CEW are drawn to these corn fields in the early green silk stage in an effort to lay their eggs (Figure 2). CEW are difficult to find during scouting, and have a variety or color variations ranging from dark brown, brown, tan, and green, and may even feature a pink hue. Adult moths are tan to light brown and feature many dark blotches, and feature a large bold spot halfway between the body and wing tip (Figure 3). For more information on CEW and the threats they pose, check out our previous newsletter: https://agcrops.osu.edu/newsletter/corn-newsletter/2019-27/corn-earworm-field-corn-watch-molds
Corn Earworm Moth Map
July 4th – July 10rd, 2023
Watching the Western Bean Cutworm
This is our third week reporting on adult Western bean cutworm (WBC) populations across Ohio. Overall, 19 counties across Ohio monitored for WBC populations using 61 total bucket traps. Most counties had less than one moth per trap (Figure 4).WBC is a common Ohio pest affecting dry beans and corn and was historically found in the western Corn Belt. However, staring in 2000, damage was seen in Minnesota and Iowa, in 2006 the pest reached Ohio. Most of the moths have been caught in the northwest and west central parts of Ohio. Adult WBC emerges in late June through early July. Adult moths can be identified by three unique characteristic markings: a white stripe on the top edge of the forewing; a light brown, tan dot on the wing; and finally a crescent-shaped mark behind the dot (Figure 5). Unlike many other pests, there is only one generation per year, with moths laying eggs in egg clusters from 5 to 200 eggs that will hatch within 5-7 days. The eggs are first white, then tan, then a dark royal purple (Figure 6). Scouting for WBC eggs is recommended when your county levels are averaging more than 7 moths per week. To scout for eggs or larvae, select 20 consecutive plants, at 5 random locations, and inspect the upper 3-4 leaves and silk for eggs. For more information regarding the Western bean cutworm, visit our previous article: https://ohioline.osu.edu/factsheet/ENT-40#:~:text=Western%20bean%20cutworm%20(WBCW)%20was,corn%20in%20Iowa%20and%20Minnesota.
Western Bean Cutworm Moth Map
July 4th – July 10rd, 2023
Exploring the European Corn Borer
This is our eighth week monitoring the European corn borer with an average of 0 IA variants and 0 NY variants being reported from July 4th- July 10th (Figure 7). In total, 9 counties across Ohio are monitoring for both ECB variants.The European Corn Borer (ECB) is a common corn pest of Ohio that bores into corn stalks; these pests cause corn stalk disease, stalk breakage, and ear drop which reduces corn yield. ECB overwinter in corn stalks, and in the early spring will emerge as moths, which then deposit the next generation on mid-whorl stage corn. These eggs hatch and first feed on foliage, before later tunneling into the mid-ribs and stalks of the corn. Male and female adult moths look different, but are typically a straw or light brown color, with a dark wavy line two-thirds of the way outer edge of the hindwing (Figure 8). For more information about the European Corn Borer visit our website: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_15_14.pdf
European Corn Borer Moth Map
July 4th – July 10rd, 2023
Crop Observation and Recommendation Network
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.
Contributors
Disclaimer
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 an accessible format of this publication, visit cfaes.osu.edu/accessibility.