Table III can be used to determine how much residue will remain on the soil surface after specific implements are used. For example, if 90 percent of the soil surface is covered with corn residue in the ecofallow period, only 63 percent will remain after a light discing. Amount of crop residue maintained by various primary and secondary tillage tools used for weed control during the fallow period. Also, the wintering effects on crop residue and the residue maintained by wheat seeders. The primary purpose of tillage is to control weeds and to prepare a seedbed for winter wheat seeding.
Excess tillage breaks down soil structure and destroys residue.
Consequently, the soil is more susceptible to wind and water erosion, surface crusting, and soil compaction. It is important that tillage operations be performed when the weeds can be easily controlled. With reduced-tillage, a tillage operation should be completed by July 1 even if not needed for weed control. This is to prevent the soil from getting so hard that penetration by tillage equipment or wheat seeders is difficult or impossible in the fall. Hard soil conditions occur with hot dry weather.