Dealing with wet fields, ruts and soil compaction

One of the challenges following a record setting year of rainfall is how to fix the ruts and soil compaction left behind.

According to Francisco Arriaga, Extension Soils Specialist with UW-Madison, the level of compaction and rutting depends on the number of field passes, equipment axle loads, type of tire (flotation, duals, or tracks), as well as soil type and structure.

“Tillage is often needed to fix subsoil compaction and rutting; however, doing tillage when soils are wet can make matters worse” Arriaga cautions.

He offers the following advice when dealing with the wet fall farm fields:

• The relative depth of compaction in wet soil depends on the level of soil moisture at the time the soil is trafficked. Keep in mind field operations when soil are very wet or wetter than field capacity will have a greater risk of rutting than they do for subsurface compaction (deeper than 6 inches).
• Therefore ruts don’t always indicate subsurface compaction. A penetrometer should be used to confirm subsurface compaction. If there isn’t subsurface compaction, there is no need for sub-soiling or deep tillage.
• Doing tillage in spots to fill deep ruts is a better approach than doing heavy tillage across the entire field. Besides, deep ruts may take two or more passes to get them filled.
• If soil conditions are still too wet after harvest to fix ruts or compaction issues, wait until soils dry out before doing additional tillage, which could mean delaying tillage until next spring. Tilling wet soils will only create more issues that lead to additional aggregate breakdown and hardening of the soil.  Arriaga notes there is limited research on tilling frosted soils, and results have been mixed. The biggest factor is the amount and depth of frost present in the soil. Avoid making clods.
•  Clay smearing is more likely to happen when tilling wet soils. Soils with smeared clay will have a reduced infiltration capacity and can create issues for seed germination.

RELATED: Experts share tips on soil compaction

Looking ahead, the UW Extension soils specialist suggests enhancing soil aggregation is a long-term strategy that will help improve the ability of a field to support farm equipment. He says timely manure applications, use of cover crops and reduced tillage or no-till practices are all effective ways to increase soil aggregation and the ability of a field to support farm equipment.

This article appeared in the Waupaca County Extension newsletter