You can't completely escape soil compaction problems in a wet spring like 2015. Running larger equipment, planting when soils may not be ready and use of loaded trucks and manure tankers all lead to compacted soils.

Corn Illustrated 12/29: Disease lesions don't mean fungicide didn't work

Working wet soils when content of soil moisture is above field capacity adds to compaction. Continuous row crops instead of rotations with crops that have differing root lengths also contribute to it.

If you farm, you're going to have soil compaction. We can't completely eliminate it. However, we can minimize it. Soil compaction is one of the main reasons for lower yields. Farmers know that soil compaction should be avoided if possible, but what can you do in a wet spring? You have to plant, even at the risk of causing some compaction.

Wait if you can: Make the first tillage pass across the field in the spring when soil conditions are right to minimize soil compaction.

One thing you can do is minimize trips across the field. Research conducted at the University of Wisconsin shows that 70% to 80% of compaction is caused on the first pass across the field. Their studies also indicated that growth and plant height is retarded. Yield losses vary from 10% to 50% in various crops.

Studies conducted at the University of Minnesota showed that soil compaction in dry years will produce stunted plants and reduced yields due to decreased root growth. Compaction in wet years will reduce soil aeration and increase loss of nitrate-N. It can also decrease potassium uptake, increase incidence of diseases and produce weaker roots and stalks.

Many ideas for reducing compaction are common sense. Avoid working when soils are wet. Early planting is good but you don't have to be the first to plant. Make sure you won't cause unnecessary compaction.

Restricting traffic to certain lanes should help on most of the farm. Practice controlled traffic and use the same path every year. Use of roads or headlands is recommended. 

Addition of organic matter helps improve soil structure and reduce compaction. Use of cover crops and crop rotation can help. Various crops have different root length and structure, and mine different layers of soil, improving yield potential.

Corn Illustrated 12/22: Apply fungicides earlier rather than later around tasseling

Tillage radishes seeded as a cover crop grow 12-24 inches long and one to two inches thick. Their roots penetrate compacted layers, and add organic matter and hold nutrients, even though they die off during winter.

If compacted layers are deeper than 12 inches, sub-soiling is recommended by some. We have to constantly fight this essential evil if we want to improve crop yields! 

Nanda is Genetics and Technology Consultant for Seed Consultants, Inc. Email him at [email protected] or call him at 317-910-9876.