BROOKINGS, S.D. – There is no easy fix for field ruts left over from last fall, however SDSU Extension Soils Field Specialist, Anthony Bly, said there are ways to mitigate the issues associated with ruts before planting begins.
And, deep tillage is not the answer.
“It’s often assumed deep tillage is the best fix for ruts and compaction, but in this case deep tillage may be more of the culprit than the cure.”
He explained that when soils experience compaction like we see in wheel tracks, a lasting impact is made, often resulting in a few inches to several feet of compaction in those areas.
The degree of compaction depends on many factors, including how saturated the soils were when harvest occurred. “The percent of soil pores filled with water versus air can change the level of compaction,” Bly said. “Deep ruts are usually noticed first. But, keep in mind, even shallow ruts of a few inches can cause issues with optimal seed depth during planting if they exceed planting depth.”
Before taking action, Sara Bauder, SDSU Extension Agronomy Field Specialist said it is best to survey your fields and determine if your rutted areas are severe enough to effect planting before taking action.
Allow soils to dry
Before hooking up tillage equipment, it is important to allow soils to dry.
“Attempting to repair ruts while soils are still wet may only complicate matters,” Bauder said. “The act of repairing ruts will work best after the top 2 to 4-inches of top soil are dry. Otherwise, if soils have not had the opportunity to dry properly, farmers could make issues worse with smeared, compacted soil surfaces.”
Another helpful option for some growers, may be to allow winter annual cover crops or volunteer crops to grow until the ground is dry enough for planting. At that time, chemically burn down the growing plants before no-tilling the cash crop.
“This can help producers looking to dry out saturated soils prior to planting this spring,” Bauder said. “However, careful management of these types of practices is needed for success.”
Choose target areas to lightly till
The key to repairing ruts, Bly said, is targeting specific areas rather than taking a pass at the entire field. “Essentially, make the field plantable without full-width tillage.”
Ideally, Bly said farmers should shallowly fill in the areas where ruts occurred, rather than disturbing the entire soil layer down to the bottom of the tire rut.
“Deep tillage will disturb the soil at lower depths with excessive moisture and may cause even more compaction damage,” Bly said.
Keep in mind, when filling in ruts, there is likely nothing growing in the soils, so farmers are solely relying on evaporation to dry out the soils. Therefore, pulling up additional moisture is not going to help.
Bauder said simply using a light tillage pass, such as a vertical tillage tool, light disc, soil finisher or harrow (in shallow rut cases) is going to be most ideal to fill in ruts and prevent further compaction.
In some cases, with very deep ruts, multiple tillage passes may be needed. Be sure to allow time (at least two weeks) in-between passes for drying before tilling slightly deeper than the previous pass. See Figure 1 as an example of a multiple tillage pass repair. Just level the surface to make planting possible this spring and look towards dealing with any major compaction issues next fall.
Consider no-till and other preventative actions
Although we cannot change what happened last fall, some options can help avoid soil compaction and improve soil structure moving forward.
“In many southeastern South Dakota fields last fall, it became apparent some producers with established no-till fields, who followed the main soil health principles, were able to enter fields earlier and had minimal, to no issue with field ruts, compared to conventionally tilled neighbors,” Bly said.
In general, Bly explained, tillage practices result in poor soil structure and increased compaction due to the disruption of soil aggregates and good soil structure.
“Moving in the direction of no-till can help producers build soil structure, giving soils a stronger shear strength and structure,” she explained. “These properties allow producers to get out into fields faster during wet times.”
However, Bauder explained, these changes do not happen overnight. “There are many additional soil health principles that, when added to minimal soil disturbance, can greatly improve the health and productivity of soils.”
For more information on these topics, visit the Resource page on the South Dakota Soil Health coalition webpage.