As its name implies, conservation tillage conserves soil by reducing erosion. In the Midwest, erosion by water is the primary concern, whereas western regions of the country are more susceptible to wind erosion.
Soil erosion removes the productive layer of topsoil, reducing crop yields and land value.
Soil removed from fields eventually ends up as sediment in streams, rivers, or lakes. Sediment collects in surface waters, reducing their water-holding capacity. Some crop nutrients and pesticides attach to soil particles and are carried and deposited in waterways along with the soil. Conservation tillage practices reduce erosion by protecting the soil surface and allowing water to infiltrate instead of running off. Table 1 shows the relationship between residue cover and soil loss.