Impact of Corn Planting Depth on Day of Emergence, Ear Size, and Yield Potential

Impact of Corn Planting Depth on Day of Emergence, Ear Size, and Yield Potential - 2022

• The primary objective of this study was to identify the impact of corn planting depth on corn growth.
• Growers can only establish optimal planting depth at planting, primarily via proper decision making, planter maintenance, and planter adjustment.
• Planting depth can impact seedling emergence, establishment, rooting mass, and rooting volume.
• Deeper depths can aid in reducing bird predation of emerging corn seedlings.

• For grain yield, all plots were harvested using commercial machinery.
• For ear size, sample ears were hand harvested, shelled, and corrected for moisture content.
• Grain weights adjusted to 15.5% moisture content.
• Emergence Data
  • Plots were sampled for emergence at mid-morning each day (Figures 1, 3, and 4).
  • Two, 15-feet samples per plot tagged as emerged.
    

• Plot information
  • Heaven South
    • Minimal bird predation.
    • Emergence occurred under near normal weather conditions.
    • Emergence was staggered over nine days and was more so with the 2.5-inch depth.
    • Emergence began on 4/6/22 and continued through 4/15/22.
      • Seedling establishment on 4/20 was 90.5% for seeds planted at a depth of 2.5 inches and 92.1% for seeds planted at a depth of 1.25 inches (Figure 5).
    • No clear trend in ear size was observed based on planting depth (Figure 6).
    • Yields (Figure 7)
      • Similar for the two planting depths.
        • The 1.25 depth seeds averaged 224 bu/acre.
        • The 2.5 depth seeds averaged 225 bu/acre.

• Field C2
  • Heavily influenced by bird predation.
  • Soil crusting prevented emergence until crusting was reduced by rainfall which enabled emergence to begin quickly.
  • Emergence began on 4/6/22, was nearly complete by 4/8/22, and determined to be complete on 4/12/22 (15 days after planting).
    • Seedling establishment on 4/12 was 88.2% for seeds planted at a depth of 2.5 inches and 64.6% for seeds planted at a depth of 1.25 inches (Figure 8).
    • The 1.25-inch planting depth emergence and stand establishment was heavily reduced by bird predation.
    • The 1.25-inch depth seed did emerge quicker and was mostly complete within 3 days.
    • The 2.5-inch depth seed had staggered emergence over the 5-day period.
  • No clear trend in ear size was observed based on planting depth (Figure 9).
  • Yields (Figure 10)
    • The 1.25 depth seeds averaged 108 bu/acre.
    • The deeper planted seeds averaged 216 bu/acre.
      • Higher because of the increased harvest population, less bird predation, and increased rooting mass and volume.

• These data demonstrate the importance of proper planning and planting depth in corn production.
• Deeper planting depth can help:
  • Reduce bird predation
  • Provide for greater rooting mass and rooting volume
  • Improve standability and the uptake of fertility and water
• Proper planning is essential in corn planting process and can only be changed at that time
• As much as 100% yield improvement was observed in these trials with deeper planting at the C2 field because of reduced bird predation.