Tips for managing and minimizing post-harvest field ruts in fields

More often than not, harvest will yield field ruts in addition to grain, especially after Iowa’s record-setting September rains. Before managing these ruts with tillage, farmers should consider several factors, said State Agronomist Barb Stewart of the USDA Natural Resources Conservation Service (NRCS) in Des Moines.

Before performing any tillage, first double check if this operation would still meet highly erodible land conservation compliance requirements. “When in doubt, please visit your local NRCS office,” said Stewart.

Second, wait as long as possible to start tillage operations, so the soil can dry out as much as possible. Perform tillage operations when the soil at or just above the tillage operating depth is dry enough to prevent soil smearing and compaction. Iowa State University Agricultural Engineer Mark Hanna recommends the following for assessing soil moisture conditions:

• Collect a handful of soil from an area between ruts and two inches above the operating depth of the tillage tool and form it into a ball. Then throw the ball of soil as if throwing a runner out at first base. If the ball stays mostly intact until it hits the ground, the soil is too wet to till.

• Take a similar soil sample in your hand and squeeze the soil in your fist and use your thumb and forefinger to form a ribbon of soil. If the ribbon extends beyond two to three inches before breaking off, the soil is too wet to till.

Third, consider tillage depth, said Stewart. “Deeper tillage and more aggressive operations are likely to damage soil structure, ultimately leaving soil susceptible to further compaction,” she said. On sandier soils, tillage should be six to eight inches deep to fill in the ruts. On heavier soils, tillage should be as shallow as possible.

Fourth, target tillage. If ruts are uniformly distributed across the whole field, some type of tillage may need to be done on the whole field. In many cases, however, ruts are localized and only need localized repair.

Last, but not least, consider planting cover crops after tillage. “The living root of the cover crop will start rebuilding soil structure,” said Stewart. “This will help you get a head start on preventing future issues with compaction.”

While fall tillage can help alleviate the negative impacts of field ruts, the best defense is building soil health and soil aggregate stability. Soil can better resist compaction by eliminating tillage, increasing organic matter content, and maintaining a living root system in the soil for as much time as possible.

For more information about fighting compaction with improved soil health or planting cover crops, go to, or visit an NRCS field office.