Author: John

Wheat Foliar Diseases and Head Scab Risk

Wet conditions have stalled corn and soybean planting but may be ramping up the risk of foliar disease in wheat.

Ohio’s wheat crop is either at or past Feeke’s Growth Stage 10 (boot) and now is the time to scout fields if you have not already. Foliar diseases like Septoria leaf spot and powdery mildew thrive in cool, wet conditions and can potentially reduce grain yield and quality by damaging the flag leaf.  When scouting for Septoria leaf spot, look for irregular brown blotches that may become bleached in appearance and contain small, blackish dots (fungal fruiting bodies). The main sign of powdery mildew is fluffy, whiteish-gray powdery growth (called pustules) on the leaf surface and lower stem. As the pustules age they will become covered with black dots on the surface.

As temperatures increase this week, keep an eye out for other potential foliar diseases such as Stagonospora leaf blotch and leaf rust. Stagonospora leaf blotch symptoms develop when temperatures are between 68- and 81-degrees Fahrenheit and typically appear as brown, lens-shaped lesions surrounded by yellow halos. Leaf rust also prefers warmer temperatures coupled with rainy, humid conditions and can be diagnosed by its round, orangish-red pustules scattered across the leaf surface.

If disease is present and conditions remain favorable for further disease development, consider a fungicide application between Feekes Stages 8 through 10 to prevent disease from reaching the flag leaf. Fungicide options can be found at https://cropprotectionnetwork.org/publications/fungicide-efficacy-for-control-of-wheat-diseases.

Once wheat reaches flowering, Fusarium head blight or head scab becomes the main concern. Risk for head scab infection and deoxynivalenol (DON) contamination is greatest when wet, humid conditions coincide with flowering. To estimate the risk of infection in your area, utilize the Fusarium Risk Assessment Tool just prior to flowering. It is available at http://www.wheatscab.psu.edu/ If a susceptible variety is planted and the risk of FHB is moderate to high, consider a fungicide application of Prosaro, Caramba, Proline, or Miravis Ace at Feekes Growth Stage 10.5.1 (early flowering, Figure 3) or within the first 4 day after Feekes 10.5.1.

Soybean Seedling Disease

Soybean seedling diseases are often the cause of reduced stands and can cause significant economic losses on an annual basis. Diseased seedlings are often less vigorous and severe stand loss may require replanting of affected areas.  So far, this spring, the persistent wet weather we have been experiencing has created ideal conditions for the onset of early-season soybean seedling diseases.  Diagnosing seedling diseases in the field can be difficult since the symptoms of various seedling blights are similar, and seedlings often decompose quickly.  Since it’s too wet to plant, now is a great time to scout your existing emerged fields for stand issues.

Below are common diseases we can find in Knox County.

Fusarium Root Rot

Many Fusarium species reside in the soil and can infect soybean. Infected plants may be stunted and spindly with brown or black lesions on the roots and poorly developed root systems.

In severe cases, seedlings may die before emerging. Species of Fusarium can infect plants under a wide variety of environmental conditions. Fusarium root rot is often associated with stressed plants.

Rhizoctonia Seedling Blight

Is caused by the fungus Rhizoctonia solani. The characteristic symptom of Rhizoctonia seedling blight is a reddish-brown lesion on the lower stem or hypocotyl, usually at the soil level. Lesions on the diseased stem appear sunken (canker-like) and dry, and can girdle the hypocotyl. Continue reading Soybean Seedling Disease →

2025 Wheat Fungicide options

Our current weather patterns may increase the disease potential for our wheat crop this year.  Since its too wet to plant, now would be a great time to scout your wheat fields.  If disease is present or if conditions remain favorable for further disease development, you may need to consider a fungicide application.   The table below contains the 2025 Wheat Fungicide Efficacy ratings .

Click here to download a PDF copy of this table

USDA to Open General and Continuous Conservation Reserve Program Enrollment for 2025

The U.S. Department of Agriculture (USDA) today announced several Conservation Reserve Program (CRP) enrollment opportunities for agricultural producers and landowners. USDA’s Farm Service Agency (FSA) is accepting offers for both the General and Continuous CRP beginning today through June 6, 2025.

CRP, USDA’s flagship conservation program, celebrates its 40th anniversary this year. For four decades, CRP has provided financial and technical support to agricultural producers and landowners who place unproductive or marginal cropland under contract for 10-15 years and who agree to voluntarily convert the land to beneficial vegetative cover to improve water quality, prevent soil erosion and support wildlife habitat. The American Relief Act, 2025, extended provisions for CRP through Sept. 30, 2025.

“With 1.8 million acres available for all CRP enrollment this fiscal year, we are very aware that we are bumping up against the statutory 27-million-acre statutory cap,” said FSA Administrator Bill Beam. “Now more than ever, it’s important that the acres offered by landowners and those approved by USDA address our most critical natural resource concerns. With the limited number of acres that we have available, we’re not necessarily looking for the most acres offered but instead prioritizing mindful conservation efforts to ensure we maximize the return on our investment from both a conservation and economic perspective.”

General CRP (Signup 64)  Continue reading USDA to Open General and Continuous Conservation Reserve Program Enrollment for 2025 →

Wheat Management for Spring 2025

Today managing your wheat crop requires knowledge of the different growth stages of the plant.  Growth stage identification is critical for scouting and proper timing of fertilizer and pesticide applications.  Each week throughout the rest of the growing season I will discuss the various wheat growth stages I am seeing in our wheat fields and management issues at each stage.  This week I will focus on Feekes 9 and 10. Most of our wheat has progressed to the Feekes 9 growth stage,  some fields are or soon will be in Feekes 10 growth stage.

Feekes 9 – Ligule of flag leaf visible.

The flag leaf is completely emerged from the whorl. Flag leaf and the next-to-last leaf (penultimate leaf ) combined account for 70 to 90 percent of the photosynthates used for grain fill and must be protected for the plant to develop to its full potential.

 

Management.

Scout for insects and diseases. Consider a fungicide application to protect the flag leaf if foliar diseases are present on the lower canopy. Nitrogen application can increase grain protein levels.

Feekes 10 – Boot.

The head is inside the leaf sheath giving it a swollen appearance.  The flag leaf sheath and peduncle elongate and the developing head is pushed through the flag leaf sheath.  Temperatures below 28 degrees Fahrenheit may cause damage to the developing head.

 

Management.

Scout for insects, weeds, and diseases. Application of 2,4-D after wheat reaches the boot stage of growth can result in trapped heads, missing florets, or twisted awns.

Wheat Management for Spring 2025

Today managing your wheat crop requires knowledge of the different growth stages of the plant.  Growth stage identification is critical for scouting and proper timing of fertilizer and pesticide applications.  Each week throughout the rest of the growing season I will discuss the various wheat growth stages I am seeing in our wheat fields and management issues at each stage.  This week I will focus on Feekes 7. Most of our wheat has progressed to the Feekes7 growth stage, some fields are approaching Feekes 8 growth stage and beyond.

Feekes 7 Growth Stage – Second Node Visible.

At the Feekes 7 growth stage, the second node is visible above the soil surface. These nodes are usually seen as clearly swollen areas of a distinctly different (darker) shade of green than the rest of the stem. Wheat will still respond to nitrogen fertilizer applied at Feekes 7 if weather prevented an earlier application; however, mechanical damage may occur from applicator equipment. A video demonstrating for identifying Feekes 7 and 8 growth stages can be found here: https://www.youtube.com/watch?v=bnV57AhUt-Y&list=PLYlh_BdeqniJ8oD8TnyGhQHRd96ptV0Yt&index=2

Management

Plant growth regulators may be applied at this growth stage.  Scout for insects, weeds, and diseases.

2025 Second Quarter Fertilizer Prices Across Ohio

The second quarter results from a survey of Ohio fertilizer retailers showed prices in Ohio were generally lower compared to the national averages reported by Progressive Farmer – DTN (Quinn, April 2025). The survey was completed by nine retailers, representing nine counties, who do business in the state of Ohio. Respondents were asked to quote spot prices as of the first day of the quarter (April 1st) based on sale type.

The survey found the average prices of fertilizer were lower in Ohio compared to the national prices for all major fertilizers except DAP. However, only two were significantly lower (more than 5%): 28% UAN was 10% lower and 10-34-0 APP was 6% lower than the national average. The national average price for DAP was the same as in Ohio.

When compared to prices from the last quarter’s Ohio survey, three fertilizers were up significantly (more than 5%): 28% UAN, up to $341/ton from $292/ton; urea, up to $561/ton from $491/ton; and potash, up to $449/ton from $415/ton.

When compared to the April 2024 average Ohio prices, the April 2025 average Ohio prices were slightly lower for anhydrous, 28% UAN, MAP, DAP, and potash. Ammonium sulfate is the only product that saw a significant price increase (+20.2%) in the last year.  Urea, ammonium thiosulfate, and poultry litter remained relatively unchanged (+/-1%) from one year ago.

The chart below (Table 1.) is the summary of the survey responses. The responses (n) are the number of survey responses for each product. The minimum and maximum values reflect the minimum and maximum values reported in the survey. The average is the simple average of all survey responses for each product rounded to the nearest dollar. We recognize that many factors influence a company’s spot price for fertilizer including but not limited to availability, geography, volume, cost of freight, competition, regulation, etc.

Due to low responses, diesel fuel prices were not included in Quarter 2 survey results. If you are a retailer interested in participating in this study, please contact Amanda Bennett at bennett.709@osu.edu.

Click here to read PDF version of this article

Corn-to-Soybean Yield Ratios Across Midwestern States

Source: farmdoc daily (15):84, Department of Agricultural and Consumer Economics, University of Illinois at Urbana-Champaign.

Summary

While corn and soybean yields have increased over time, corn-to-soybean yield ratios generally have not trended up or down at the national or state levels in the 21st Century. However, there does exist variation in relative yields across states. States in the central Corn Belt region (Illinois, Iowa, Indiana) tend to have higher corn and soybean yields than states in the western Corn Belt and Great Plains (Kansas, North Dakota). In relative terms, as measured by the corn-soybean yield ratio, corn is relatively more productive (higher yield ratios) in the states with lower average corn and soybean yields.

 

Both corn and soybean yields have trended up over time at the national and state levels. Relative yields, as measured by the corn-to-soybean yield ratios, have not trended up or down at the national or state levels over the last 25 years. Differences in yield levels and relative yields exist across states. States with higher corn yields also tend to have higher soybean yields.  States with lower yields tend to have higher corn-to-soybean yield ratios.

U.S. Corn-to-Soybean Yield Ratios

Relative yields of corn and soybeans are often evaluated using a corn-to-soybean yield ratio. We used yields reported by the National Agriculture Statistics Service (NASS) for harvested acres. In 2024, the U.S. yield for corn was 179.3 bushels per acre, while the U.S. yield for soybeans was 50.7 bushels per acre. The 2024 corn-to-soybean yield ratio was 3.54, which equals the 179.3 corn yield divided by the 50.7 soybean yield. This ratio means that one acre yields 3.54 times more bushels of corn than of soybeans.

Since 2000, the U.S. corn-to-soybean ratio has averaged 3.49, with much variation around that average. The highest U.S. ratio of 4.19 occurred in 2003 when soybeans were particularly hard hit by aphids and other pest infestations. The lowest ratio of 3.08 occurred in the 2012 drought year. The extremely dry weather in 2012 had larger adverse impacts on corn, with rain occurring in August helping soybean yields. Statistical tests suggest that the corn-to-soybean ratio has not been trending up or down since 2000. Continue reading Corn-to-Soybean Yield Ratios Across Midwestern States →

Effect of standing water and saturated soils on corn growth

Source: Agronomy eUpdates

 

If corn has been planted, standing water or saturated soil conditions in areas of a field can produce impacts now or later for corn. Periods of early-season water saturation can cause immediate problems for small corn plants and can have season-long implications as well. Hopefully, the affected areas are small and confined to spots that are low-lying or poorly drained. While heavy rains and respective standing water have been limited to areas of northwest, northeast, and southeast Kansas, the coverage is expected to increase into mid-May. Precipitation is forecasted across most of the state with an emphasis on western Kansas, where upwards of 2-3 inches is possible. In addition to this above-normal moisture, temperatures will be cooler than normal with extensive periods of clouds. Thus, the extent of inundated corn may potentially increase as a result.

Factors affecting flood damage to corn include

  • corn growth stage,
  • the duration and frequency of saturated or standing water, and
  • air and soil temperature while water is standing.

Saturated soil after corn emergence

After corn emerges, saturated soils inhibit root growth, leaf area expansion, and photosynthesis because of the lack of oxygen and cooler soil temperatures. Yellow leaves indicate a slowing of photosynthesis and plant growth. Leaves and sheaths may turn purple from the accumulation of sugars if photosynthesis continues but growth is slowed. Corn plants can recover with minimal impact on yield if the plants stay alive and conditions return to normal fairly quickly.

Although root growth can compensate to some extent later in the season, a saturated profile early in the season can confine the root system to the top several inches of soil, setting up problems later in the season if the root system remains shallow. Corn plants in this situation tend to be prone to late-season root rot if wetness continues throughout the summer, and stalk rots if the plants undergo mid- to late-season drought stress. Plants with shallow root systems also become more susceptible to standability problems during periods of high winds.

Tolerance of young corn plants to full submersion

Young corn plants can tolerate only a few days of full submersion. In some cases, symptoms and stand problems seen late in the season may trace back to flooding when the plants were young. Before V6, when the growing point is at or below the soil surface, corn can survive only 2-4 days of flooding. The chances of plant survival increase dramatically if the growing point was not completely submerged or if it was submerged for less than 48 hours. After 48 hours of soil saturation, soil oxygen is depleted, and critical plant functions (photosynthesis, water uptake, and nutrient uptake) are impaired.

Thus, young corn plants are more susceptible than corn beyond the V6 stage, when the plants are taller and the growing point is above the surface. Research has demonstrated yield reductions from early-season flooding ranging from 5% to 32%, depending on soil nitrogen status and duration of flooding.

Complicating factors

Temperatures can influence the extent of damage from flooding or saturated soils. Cool, cloudy weather limits damage from flooding because growth is slowed and because cool water contains more oxygen than warm water. Warm temperatures can increase the chances of long-term damage.

Silt deposition in the whorls of vegetative corn plants can inhibit the recovery of flooded corn plants. Enough soil can be deposited in the whorl that the emergence of later leaves is inhibited. A heavy layer of silt on leaf surfaces can potentially inhibit photosynthesis or damage the waxy surface layer of the leaf (cuticle), making the leaves subject to drying out. New leaves should not be affected if they can emerge normally. Ironically, what is often best for the silt-covered plants is to receive a small shower to help wash off the leaves.

In some instances, the soil in the whorl may contain certain soft-rotting bacteria. These bacteria can cause the top of the plant to rot. The whorl can easily be pulled out of a plant infected with these soft-rotting bacteria. In addition, a rather putrid odor will be present. These plants will not recover.

Disease considerations

Flooding can increase the incidence of moisture-loving diseases like crazy top downy mildew. Saturation for 24 to 48 hours allows the crazy top fungus spores found in the soil to germinate and infect flooded plants. The fungus grows systemically in the plant, often not causing visual symptoms for some time. Symptom expression depends on the timing of infection and the amount of fungal growth in the plant. Symptoms include excessive tillering, rolling and twisting of upper leaves, and proliferation of the tassel. Eventually, both the tassel and ear can resemble a disorganized mass of small leaves, hence the name “crazy top.”

Other concerns: Denitrification, cold weather crown stress, green snap, and root lodging

Saturated soils can also cause loss of N fertilizer by either denitrification (loss of N to the atmosphere, mainly as nitrous oxide gas) or leaching (movement of N beyond the rooting zone). For any of these losses to occur, N should be present in the mobile nitrate (NO3–) form. Depending on the fertilizer application time and source, most of the N may still be in the stable ammonium (NH4+) form. However, the conversion to nitrate happens quickly as soil temperature continues to increase. Under wet spring planting conditions, corn may respond to in-season N applications if a large portion of early-applied N is lost to these processes. If corn remains N deficient later in the season, expect considerably higher levels of stalk rot.

Another condition associated with extended periods of cool, wet soils is commonly referred to as cold weather crown stress. Internal stalk cells in the crown nodes can become “leaky” when cell membranes become chilled and oxygen is limited because of the saturated soils. Hybrids with “southern” genetics are more susceptible to this problem than are northern types. Plants may recover from this damage, but they will be much more susceptible to stalk rot later in the season if hot, dry temperatures occur, since water and nutrients cannot be efficiently moved through the damaged crown.

Sidewall compaction from planting into wet soils

Source: Agronomy eUpdates

Figure 1. Sidewall and seed zone compaction in heavy clay soil.

Conducting field work — including planting, tillage, or traffic in general — after wet weather can cause soil compaction, particularly sidewall compaction in the seed furrow. The worst cases of sidewall compaction are seen after a field has been planted when the soil was too wet, followed by a period of dry weather. If the soil stays moist, the roots can usually grow through the walls of the seed furrow. However, if the soil gets dry, the roots can have a harder time growing through that seed furrow wall, and instead grow along the furrow, resulting in what is referred to as sidewall compaction.

With corn, the plants might look fine for a while, but the symptoms of this problem will probably show up after the plants reach several inches tall. Symptoms can mimic drought stress, nutrient deficiency, or both.

Since there are not any good ways to fix sidewall compaction once it exists, the best practice would be to avoid creating the problem in the first place. This means waiting until soils are dry enough to plant. The way to test for this is to dig down to the desired planting depth and make a ball with the soil. Next, see if the ball will crumble or crack apart, or if it deforms like molding putty. If it crumbles, it is ready to plant. If it deforms, it would be best to wait before resuming field operations. Even waiting as little as half a day could make a big difference.

Other considerations

  • Planting too shallow: Planting shallow in wet soil may lead to wheel compaction below the seedling depth. This results in limited downward root growth and seeds growing horizontally.
  • Too much down pressure: If you must work in wet soil, then the down pressure of the row unit and press wheels needs to be reduced to limit compaction around the seed.
  • Soil structure: Tilled soils often lack proper soil structure, causing the standard closing wheel to pinch the sidewalls over the seed from additional pressure. This is frequently a concern in heavier-textured soils, i.e., higher clay content.