If you already contributed to compaction by harvesting on wet soils, don't make it worse by trying to fix the problem before the soil dries.
Paul Jasa, University of Nebraska Extension engineer, recommends evaluating soil moisture conditions before filling in ruts left by harvesting equipment and gullies left by heavy fall rains.
Spot tillage can be done to smooth fields or relieve compaction, but wait until the soil dries, he says. "The soil may appear dry on the surface, but it's probably too wet at tillage depth to effectively reduce compaction."
Jasa recommends shallow spot tillage rather than whole field tillage.
Driving on or tilling a wet soil creates compaction when wet soil particles are lubricated and easily slide under the weight of tires and implements. Compaction is the loss of pore space between the soil particles, and if that pore space is lost, it reappears on the soil surface as the rut or as a denser soil at a reduced elevation.
"Wait as long as possible for the soil to dry before lightly tilling very shallow to smooth the ruts," Jasa says. "Resist the temptation to fill deeper, thinking that you will get rid of more compaction. The soil will be wetter below the soil surface and more readily compacted."
"Unless something is done to anchor the soil when the gullies are filled, they will simply wash out again," he explains. "Seeding a cover crop in these areas will help anchor the soil, especially on sloping ground."
Jasa suggests using a center pivot track filler to fill ruts because it will disturb less soil.
"Mounting a 12-volt spinner seeder in front of the track filler could seed a cover crop at the same time. The roots of the growing cover crop will help reduce compaction and help build soil structure."