High Input Corn Management

Trial Overview

  • Every year, farmers question which inputs will give the highest return on their investment. To assist farmers with these decisions, a high input corn study was set up to evaluate the potential benefits of various inputs.

Research Objective

  • To determine which inputs maximize irrigated corn yields and economic return.
Soil Type
Previous Crop
Tillage Type
Planting Date
Harvest Date
Potential Yield
Planting Rate
Gothenburg, NE
Hord silt loam
Strip tillage
280 bu/acre
32K, 38K, 44K

Site Notes:

This study consisted of low input (normal management, NM) and high input (intensive management, IM) base treatments with different inputs added or removed (Table 1).Three corn products were assessed: one 116 RM corn product and two 114 RM corn products. Each product was tested with each treatment totaling 30 treatments.Treatments were randomized with four replications.Weeds were managed uniformly across the study and no insecticide was applied.Soil test: organic matter 3.0%, pH 6.6, nitrogen (N) - 40 lbs/acre residual in 2 ft., phosphorus (P) - 39 ppm MP3, sulfur (S) - 26 ppm, zinc (Zn) - 2.0 ppm.Plants that died prematurely, green-snapped plants, stalk-lodged plants, and root-lodged plants per plot were recorded prior to harvest.



Understanding the Results

Figure 1. Average corn yields in the different treatments
  • Yields
  • Individual corn products did not respond differently to treatments so results are summarized across treatments.
  • A fungicide application at VT provided the most value in terms of yield.
              -  When added, the fungicide application increased yield by 13 bu/acre over the base NM system.
              -  When the fungicide application was removed from the base IM system, yields decreased by 25 bu/acre.
              -  A fungicide application at VT also increased yields in 2015 and 2016 demonstration trials as documented in previous Learning Center Reports.
  • Neither the split N application nor additional S and Zn significantly affected yields.
              -  In a 2015 Learning Center Report, adding S and Zn increased yields.
              -  In a 2017 Learning Center Report, a split application of N increased yield when applied through a subsurface drip irrigation system.
              - The soil in this trial had relatively high fertility levels based on the soil test, indicating that corn products may not respond much to additional fertility.
  • Across the different seeding rates, 38,000 seeds/acre provided the best performance.
              -  In a 2016 Learning Center Report, the 44,000 seeds/acre rate increased yield significantly.
  • Plant Quality
  • No differences were observed across treatments for green-snapped plants, plants that died prematurely, or stalk-lodged or root-lodged plants.
  • Economics
  • When using current corn prices of $3.00/bu, the treatment that provided the highest return over investment was the NM plus fungicide treatment. If corn prices increase, this treatment would continue to provide the greatest economic advantage up to a corn price of $9.00/bu.
  • For the IM options, the IM without fungicide treatment would cost the farmer close to $140/acre relative to the NM plus fungicide treatment.

What Does This Mean for Your Farm

  • Farmers should consider using a fungicide application at the VT growth stage as it has consistently provided value across multiple corn products and multiple years.
  • Increasing seeding rate can increase yield and provide more value to the farmer as long as the seeding rate is increased on an appropriate corn product. Please consult your local seed sales team for individual corn product seeding rate recommendations.
  • The value of other inputs, such as a split N application or additional S and Zn, have been more variable over the years.