Expert shares tips on soil compaction management

Gloria Hafemeister
A wet harvest season followed by a winter of lots of snow is leaving some farmers wondering about whether they will have soil compaction this year from running harvesting equipment on wet ground.

MAYVILLE - A wet harvest season followed by a winter of lots of snow is leaving some farmers wondering about whether they will have soil compaction this year from running harvesting equipment on wet ground.

Francisco Arriaga, Soil and Water management specialist at the University of Wisconsin-Extension cautions, “Don’t assume sub-soiling is needed. Just because your field has ruts, it doesn’t mean that there is sub-soil compaction. Don’t run the sub-soiler if it is not needed.”

Speaking at a gathering of about 100 farmers at a healthy-soil meeting in Dodge County on April 3, Arriaga said the freeze-thaws cycles this winter and early spring probably helped loosen some soil but only on the surface. Those concerned about sub-soil compaction, should check conditions with a penetrometer first.

Arriaga points out that this can help save time and money (if compaction is not detected) and can help setup the depth of the sub-soiler operation if compaction is found.

Arriaga offered some tips for soil compaction management.

  • Waiting for better soil moisture conditions is best, but not always possible.
  • Reduce axle loads and maintain low tire pressure.
  • Manage equipment traffic patterns to contain and reduce soil damage.
  • Surface tillage may be needed to address ruts.
  • Cover crops can help.

The meeting was hosted by Richard Wondra who transitioned out of dairy to cash cropping in 2002. He said with the help of Jim Fanta who had been his agriculture instructor at Mayville High School and then served as Dodge County’s crops and soils agent, he got started with no-tilling.

Wondra admits he wasn’t patient enough to let the soil dry before planting. He tried a variety of methods including using sulphur to loosen the soil.

He tried planting tillage radishes on fields where he raised vegetable crops. Now he is interested in learning more about incorporating other types of cover crops so he agreed to host the field day sponsored by the Healthy Soils-Healthy Water group in Dodge County.

Many of those in attendance have been practicing no-till practices with a handful including cover crops in their soil-management plans. Those growers shared their experiences with others at the meeting and also took home some new information.

Adam Latsch of Lake Geneva said, “I couldn’t afford the tillage equipment when I went into farming on my own a few years ago so I got into no-till. I found that by adding cover crops it worked even better.”

Bill Nass has been no-tilling for 30y years on his Watertown farm.

“I have no ruts in my fields from last fall’s harvest while some of my neighbors’ fields have water standing in the tracks,” he said, adding that he has a lot of earthworm activity on my farm. "That helps (the soil) a lot.”

While Arriaga agrees that there are numerous advantages to no-till, he says he is not totally opposed to conventional tillage if it is done properly and the equipment is set up right.

When there are surface ruts, he suggests waiting until the soil is dry enough so it is friable.

“You might have to wait up to two weeks before planting to help avoid further compaction and clay smearing,” he says.

Arriaga recommends light tillage to the rutted spots only if the ruts are not field-wide. If ruts are deeper than four inches, chiseling might be needed followed with a different secondary pass to level the ground.

“Be patient," he said. "Allow the soil to dry and don’t over-work the ground. Allow the soil to recover some on its own.”

The Healthy Soils-Healthy Water group has been doing test plots on farms around the county to determine ways to avoid erosion and improve water infiltration.

Arriaga demonstrated how long-term no-till improves water infiltration and soil aggregation. When aggregates are weak, he says the soil erodes with a heavy rain or water sits on the surface, resulting in crusting.

“When that happens it’s a double whammy,” he says. “You not only lose soil and nutrients but you also have less water available later in the season for crop growth.”