Harvest variability

By Mitch Greve, Channel technical agronomist — Northwest Ohio

Producers in Ohio experienced a unique set of challenges in 2023 including delayed planting, poor emergence, drought and water stress, disease, stalk rots, and ear molds to name a few. This variability can teach farmers lessons around how to manage their crops in future years.

Planting conditions for much of the state were favorable early and not-so favorable the deeper into May that we got. Planting for success starts with good uniform soil moisture and temperature, seed-to-soil contact, and accurate delivery of seed from the planter to the soil. Most growers across the state did not have all three critical components, as weather was less than favorable in the latter half of May with drier soil conditions and delayed planting from early May rainstorms. All this variability can contribute to varying yield ranges that farmers may experience this fall.

Disease was minimal through the midway point of the season, but when we finally started receiving rainfall in August, it set us up to have a conducive environment. That conducive environment included precipitation and moderate to higher humidity, enabling gray leaf spot (GLS) to show up. A few short weeks later, tar spot started creeping in when the humidity dropped off in late August to early September. Then, in late September northern corn leaf blight (NCLB) made an appearance to help complete a trifecta of the most prominent diseases we see in Ohio corn fields. When you combine this with the late planting date for some corn and potential lack of nitrogen up-take during the early season drought stress with these leaf diseases it is a perfect set-up to begin seeing compromised stalks as plants begins to cannibalize themselves.  

Compromised stalks were witnessed from north to south in Ohio this year. Many of the cases boiled down to three issues which were: Anthracnose top dieback, Physoderma stalk rot, and crown rot/Fusarium.

In many cases all three of these issues can be traced back to soil borne pathogens that infected the corn crop early in the season. Early season rain splashed infected soil particles into the whorl of young corn plants and the disease shows up later in the growing season when the crop has a compromised immune system, due to the early season drought stress and disease that the crop is trying to fight off. Keeping the corn well fed with nitrogen, relieving stress via fungicides, and variety selection are all factors to help reduce the likelihood of seeing stalk rots.

Much like stalk rots, ear mold infections are unanticipated factors that come with growing corn. The late season rains paired with foggy mornings created another less than ideal host environment for ear molds. Ear molds began showing up late in September because of lower evening temperatures, foggy mornings, tight husks on plants, late planting date, and slow dry down. The three most common this year were Penicillium, which causes blue-green mold near the tip of ears, Diplopia which creates white mold starting at the base of ears working its way to the tip, and Gibberella which is pink-white mold starting at the tip of ears and is the main driver for vomitoxin in corn. Ear molds can be caused from birds/insect damage and soil borne pathogens that live in soil. Deep tillage to break up residue and variety selection can help reduce this problem.

Harvest variability was a given in 2023 with the wide range of weather conditions and diseases that farmers across Ohio. Yield levels have still been reported as better than expected for most, but as stewards of the land there is always something new to learn. As you think about plans for next year, please keep in mind your specific challenges and how they impacted your harvest variability.