Effects of Nitrogen Management Practices on Corn Yield

Trial Overview

  • Nitrogen (N) management in corn production continues to be a subject of much research. This, in part, is due to the complexity of the nitrogen cycle with regards to its availability to plants.
  • From N application timing, to different sources and rates, to changing environmental conditions, the N practice that best optimizes corn productivity needs to be understood for sustainable operations.

Research Objective

  • To determine the response of two corn products to different N management practices.
Soil Type
Previous Crop
Tillage Type
Planting Date
Harvest Date
Potential Yield
Planting Rate
Huxley, IA
Clay Loam
225 bu/acre
34,000 seeds/acre

Site Notes:

A 105 RM and a 113 RM SmartStax® RIB Complete® Corn Blend were used for this trial. The trial was carried out in 30-inch row spacing, 6 rows/treatment with 2 replications. Nitrogen Treatments:160 lbs/acre PRE80 lbs/acre PRE + 80 lbs/acre at V5 with coulter80 lbs/acre PRE + 80 lbs/acre at V5 with 360 Y-Drop®  80 lbs/acre PRE + 80 lbs/acre at VT with 360 Y-Drop®



Understanding the Results

Figure 1. Effect of nitrogen management practice on 105 RM and 113 RM corn products.
  • The two corn products responded differently to the nitrogen treatments.
  • In all nitrogen treatments, the 113 RM product out-yielded the 105 RM product.
  • For both products, the two V5 sidedress applications substantially out-yielded the other treatments.
  • With the V5 sidedress applications, there was no difference between coulter and 360 Y-Drop® technologies in the 113 RM product. Application with coulters slightly out-yielded 360 Y-Drop® in the 105 RM product.
  • In both corn products, VT sidedressing yielded much less than the V5 application.
  • In all the nitrogen treatments, grain moisture content was about 1% lower in the 105 RM product.

What Does This Mean for Your Farm

  • Corn products respond differently to different N management systems.
  • Every growing season is different which can have a significant impact on the performance of farm inputs. During the 2017 growing season, the research site at Huxley, IA experienced drought and high temperature conditions interspersed with a few 2 to 3 inch rainfalls, a scenario that significantly affects N dynamics in the soil.
  • Growers are encouraged to perform small scale trials in their fields to understand how management practices impact economics and production.