Q. Can tillage help with better crop establishment or fertility management?
A: Crop establishment can be impacted by soil moisture and temperature, especially in areas where more warm-season crops such as soybeans and corn are grown. High soil residue levels act as an insulating layer to the soil and reduce the rate of soil temperature increase. Growers often see an increase in spring frost damage on newly emerged crops where crop residue levels are high. A tillage operation may be considered to reduce residue cover and speed soil warming; however, we may see increased potential for evaporative water loss.
Tillage operations that incorporate a great deal of high carbon-to-nitrogen ratio residue, such as cereal straw in the soil, may lead to short-term tie-up (immobilization) of nitrogen. However, this may also be overcome with increased mineralization due to the tillage operation. With most systems, we will see an advantage to placing fertilizer in a concentrated band below the crop residue layer to reduce any potential immobilization.
As with all things in agriculture, end results may differ for growers depending on many factors such as soil and environment. When considering a strategic tillage operation, consider soil moisture impact and any potential erosion considerations to determine timing and aggressiveness of the operation.
Scott Anderson, P. Ag, CCA, is a Manager of Agronomic Services with Nutrien Ag Solutions in northwest Saskatchewan.