How Your Management Can Impact Key Corn Yield Components

While a cornfield’s bushels per acre is measured by the combine, it is set months before.

Corn Growth Stages
Corn Growth Stages
(Photos/Illustration: Darrell Smith, B&M Crop Consulting, Inc, Lori Hays)

While a cornfield’s bushels per acre is measured by the combine, it is set months before. Genetics play a role, but the final yield is caused by environmental conditions and management practices.

“From an agronomy point of view, corn yield is all about ears per area, kernel number and kernel weight,” says Joe Lauer, University of Wisconsin agronomist. “The plant adjusts yield components according to environment and management influences during the growing season.”

By understanding when and how yield is determined, you can make more profitable decisions throughout the growing season.


“Of course, weather drives everything, but these issues we have more control over.”
~Joe Lauer, University of Wisconsin agronomist


How Your Management Can Impact Yield

  • Hybrid - Presence or absence of certain genetic traits
    Yield Swing: 0% to 100%
  • Rotation - Continuous crops versus rotation
    Yield Swing: 5% to 30%
  • Soil Fertility - 160 lb. versus no nutrients per acre
    Yield Swing: 20% to 50%
  • Row Spacing - 30" versus 15" has a small impact on yield. Yet growers, Lauer says, pay more attention to this than hybrids, which cause a bigger yield swing.
    Yield Swing: 0% to 5%
  • Date of Planting - May 1 versus June 1
    Yield Swing: 0% to 30%
  • Plant Density - 32,000 versus 15,000 plants per acre
    Yield Swing: 0% to 22%
  • Pest Control - For corn, Lauer says, weed management is more impactful to yield than insect control, and insect control is more impactful than diseases.
    Yield Swing: 0% to 100%
  • Harvest Timing - Oct. 15 versus Dec. 1
    Yield Swing: 0% to 22%

Source: Justin McMechan, University of Nebraska Extension

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