Keeping a protective cover of crop residue on the soil surface is the simplest and surest way to control both water and wind erosion. Residues improve infiltration of water into the soil, reduce evaporation, and help maintain organic matter. Incorporating previous crop residues leaves the soil surface exposed to agricultural runoff, which causes soil erosion. Erosion Control Residue management provides a means for limiting both soil particle detachment and removal of soil particles from the field.
Vegetative residues reduce raindrop impact and reduce the wind velocity at the soil surface.
Residues also create an intricate and complex series of diversion dams that slow water runoff rates and reduce the amount of soil particle detachment. In addition, slowing the runoff rate reduces the capacity of water to transport dislodged soil particles from the field, reducing the erosion rate even more. Moisture is conserved as more time is available for water to infiltrate the soil and evaporation is reduced by the cover on the soil surface. The amount of crop residue produced and subsequently available for erosion control depends mainly on the type and yield of the crop grown and the tillage system used. Generally, higher yields mean more residues.