Long‐term yield response of corn, wheat, and double‐crop soybean to tillage and N placement

Abstract

On claypan soils of the eastern Great Plains, yield of no‐till crops often lags yield of crops grown with tillage, especially cereals requiring sound N management. The objective of this 14‐yr study was to determine the yield response of corn (Zea mays L.), winter wheat (Triticum aestivum L.), and double‐crop soybean [Glycine max (L.) Merr.] in a 2‐yr rotation to tillage system and N fertilizer placement. Tillage, N placement, or their interaction affected corn yield in all seven‐corn crop‐years. Corn yields averaged about 25% lower with no‐till than with conventional or reduced tillage and were never greater with no‐till in any year. Nitrogen fertilization increased corn yield by increasing kernels per ear; however, corn yield increase to subsurface band (knife) N applications compared with surface (broadcast or dribble) applications was only about 10%. In the lower‐yielding no‐till system, corn yield increase to knifed N fertilization was greater than in tilled systems and may partially ameliorate the no‐till yield decline. Average wheat yield was unaffected by tillage. Adding N more than doubled wheat yield, but differences in wheat yield between preplant N placements methods were small. Average double‐crop soybean yield was unaffected by tillage with few, inconsistent differences by year. Compared with no‐till, tillage tended to increase soil P and K, but soil organic matter was just redistributed with no net increase with no‐till. Thus, tillage and N placement treatments may affect corn but have lesser effects on wheat and double‐crop soybean and soil properties in this rotation.

Too Salty or Toxic for Use: A Tale of Starter Fertilizers in Agronomic Cropping Systems

“…Wheat yields were more significant with knife application than with broadcast, but the yield differences were ≤0.5 Mg ha −1 in all cases [101].…”

“…UAN (28-0-0): 140 kg N ha −1 + 30 kg P ha −1 TSP (0-46-0) and 58 kg K ha −1 KCl (0-0-60) broadcast UAN; dribble UAN; 10 cm deep placement N fertilization at any placement method increased maize yield components (kernels per ear, grain yield), but maize yield increase to subsurface band (knife) N applications was about 10% higher than broadcast [101].…”

Reduced tillage and rotational diversity improve soil health in Missouri

“…At the regional level, increased rotational diversity had no detectable effects on soil health indicators in the Eastern Claypan region. This region is known for its poorly drained claypan soils that promote runoff and erosion (Baffaut et al., 2020), leading to a range of crop production challenges (e.g., Sweeny et al., 2022). Above‐ and below‐ground crop biomass production and the residue remaining on‐site following harvest play a critical role in soil carbon inputs (Gollany et al., 2020).…”

Urea ammonium nitrate placement methods, row patterns, and irrigation effects on corn productivity in a humid subtropical region

“…One of the factors that can impact corn grain yields is N placement methods (Sweeney et al., 2022; Touchton & Hargrove, 1982; Woodley et al., 2018). In Canada, Woodley et al.…”

“…One of the factors that can impact corn grain yields is N placement methods (Sweeney et al, 2022;Touchton & Hargrove, 1982;Woodley et al, 2018). In Canada, Woodley et al (2018) found that corn grain yields were 11% greater on average when urea ammonium nitrate (UAN) was knifed into the soil compared to the surface dribble placement method.…”