Over 40 percent of Indiana's 13.8 million acres of cropland is eroding at a rate faster than natural processes can replace it. Research shows that this erosion can be greatly reduced by maintaining a crop residue cover of at least 30 percent on the soil surface after all tillage and planting operations are completed. This type of system is known as a conservation tillage system.
Conservation tillage is one of the most effective means of cropland erosion control.
Uniformly distributed residue shields the soil surface from rainfall impact, thus reducing the tearing and washing away of soil particles. The residue also creates small dams which slow the rate of runoff, allowing more time for water to infiltrate the soil. A slower rate and reduced volume of runoff means less soil removed from the field. Residue can also protect soil from the erosive forces of wind. To what extent, however, depends on the amount of residue present and whether it is upright or flat.