Corn
Iowa leads the nation in corn production. Find the latest research-based information for corn production in Iowa as well as the basic agronomics of corn production and corn growth and development.
Corn Tools and Resources
- Corn and Soybean Field Guide
- Corn Growth and Development
- Corn Staging
- Key Corn Growth Stages
- Guide to Iowa Corn Planting
- Forecast and Assessment of Cropping sysTemS
- Corn Drydown Calculator
- Corn Nitrogen Rate Calculator
- Iowa Crop Performance Tests - Corn
- Iowa Grain Quality Initiative
- Corn Content Index
Iowa leads the nation in corn production. Find the latest research-based information for corn production in Iowa as well as the basic agronomics of corn production and corn growth and development.
Timely Insights on Corn
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August 12, 2026Content Author
The corn crop is advancing in growth stages, and farmers, agronomists, and crop scouts are all keeping a close eye on fields to monitor for the development of foliar disease. While some diseases are present in fields, pressure is significantly lower than in 2025. Many images have come in of other corn issues – some disease, some not. Questions about what is and isn’t Curvularia leaf spot, a new disease to Iowa, are by far the most common.
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August 12, 2026Authors
A recently published summary of over 15 years' worth of research reveals farmers can conserve pollinators at the edges and even inside corn and soybean fields. This conservation is in the form of prairie strips planted with native, perennial flowering plants. Prairie strips offer significant food and nesting habitat for pollinators
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August 12, 2026Authors
Pollination is complete for most cornfields in Iowa, but it is still important to continue scouting for insect pests that may be robbing corn yields as the season progresses. We do not recommend using foliar insecticides unless scouting determines a need to spray. Some pests are resistant to older active ingredients, such as pyrethroids, and careful identification will determine what product would be more effective. In addition, prophylactic use of insecticides will limit any benefits that natural enemies may provide.
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August 12, 2026Content Author
Risk of ear rot and mycotoxins in hail damaged crops
Since the crop started grain fill, there have been several reports of hail damage to crops. Apart from shredding leaves, hail can bruise ears leaving them at risk for infection by ear mold fungi and consequently mycotoxin contamination.
Past research on the effect of hail damage on ear rot and mycotoxin contamination
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August 11, 2026Content Author
Most of Iowa received some amount of rainfall this last week with totals ranging from a trace to over 4.5 inches in parts of southwest Iowa. Unfortunately, with that rain, there were also some strong winds, hail, and tornados. In addition to some crop damage from the storms, concerns about the drier conditions in northwest Iowa, late season weed flushes, corn aphids, rootworm beetles, and crop diseases were other topics of conversation this past week for ISU Extension field agronomists.
