The 2019 calendar year is coming to an end and the adverse effects to soils resulting from this crop season will loom for years to come. Heavy rain in the spring meant fields were planted in less than ideal conditions. This was followed by a series of production practices being conducted in less than ideal conditions – leading to soil compaction and surface ruts. The immediate thought is to run out and deep rip to remove compaction and fill ruts, but careful thought should be given to the process to provide benefit to the next crop year, but also avoid lasting issues for years to come.
An Aggressive Approach
The first thought when addressing ruts is to aggressively fill them in. With aggressive tillage, the natural structure and aggregate stability of the soil is destroyed. Aggregates, and overall soil structure, are the soil’s top defense against future compaction. If the field is in good condition with the exception of wheel ruts, multiple light tillage passes are best practice to fill in the ruts. Wheel ruts are not only the cause of compaction, but they are highly visible and disrupt other field practices – so they often are first to be fixed.
Compaction that extends below the surface of the soil, and often goes unnoticed, is one of the largest hindrances to growing high-yielding crops. An obvious cause of compaction is the traffic of machinery throughout the field. As equipment has increased in size and weight, compaction has been pushed deeper into the soil profile. For example, if soil conditions are wet, an axle load of ten tons can cause compaction as deep in the soil as 2 ft. Alleviating compaction at these depths is not an easy process and is often not done in a single pass.
Carefully Considered Management
In a year like 2019, rescue tillage can set the stage for a successful 2020, but be careful that management does not cause bigger issues. When farmers consider a deep tillage pass to fix compaction, the most important thing is to make sure that the soil is in the right condition to work. Running a tillage implement, especially with parabolic shanks or a winged ripper point in wet soils, will cause lateral compaction that will not be cured by the lifting or mixing process of the tillage. Also, the soil below and to the sides of the points will be prone to smearing, causing a denser, more compact soil.
Another factor to consider when addressing deep tillage is identifying the depth of the compaction. This can be done with a probe or a spade. Tillage should be performed at a depth of no more than 1 to 2 in. Below the compaction layer. We know that tillage will destroy soil structure reduce organic matter, and affect the infiltration of water among other physical and chemical properties in the soil. Limiting the tillage depth to slightly below the compaction layer will leave lower profiles in the soil undisturbed and less prone to future compaction.
Strip tillage can also be a beneficial rescue-type option this fall or spring if conditions are not right for deep tillage. If a deeper compaction layer is present and not able to be alleviated, it can limit rooting depth and nutrient availability to next year’s crop. In these situations, a strip till with banded fertility would provide numerous benefits to the 2020 crop.
Thinking Ahead
Solving short-term compaction issues in the soil may require tillage for an immediate fix, but looking ahead to future seasons will allow you to evaluate other methods to resolve soil and compaction issues. One idea includes the incorporation of cover crops into your operation. Many cover crops have a deep fibrous root system capable of helping reduce compaction issues without the use of tillage. Although they may not quickly or completely remove compaction, they create channels in the soil for water, root, and nutrient movement.
Reach out to your local Beck’s agronomist or representative to learn more about alleviating compaction issues on your farm.
~Jon Skinner – Field Agronomist