Are your soils compact?
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
With harvest operations comes trafficking over the fields by combines, tractors, wagons, grain carts, trucks etc. With trafficking comes soil compaction. The degree of compaction that occurs depends on soil moisture. Excessively wet soils will compact more than dry soils. The heavier the load the deeper the compaction occurs. Wider tires tend to spread the weight over a larger area so compaction occurs at a shallower depth. Compaction is most evident during harvest, but compaction may also have occurred during seedbed preparation. Chiseling or subsoiling can be done to help alleviate the effects of compaction, but prior to doing this find out at what depth the compact layer occurs. Studies have shown that chiseling two inches below the compaction zone or depth is very effective in breaking up the compaction layer. Chiseling deeper than this depth provides no additional benefit, and uses a lot more fuel. The presence of a compaction layer and its depth can be determined with a tile rod or even a soil probe when there is good soil moisture. An increase in resistance to pushing the rod in the ground is an indication of compaction. Some consultants may have a penetrometer to use that measures the actual resistance the rod encounters as it is being pushed into the ground. Probe the soil in several different spots in a field to determine whether not compaction is a concern or the depth of compaction. Also, check the soil moisture at the depth of subsoiling. The soil should break apart when handled and not stick together in a clump when squeezed. If the soil is too wet, subsoiling will not be of benefit. The shanks should shatter the soil and not create a smeared channel.