Looking Ahead: Expect To See Sidewall Compaction
The calendar says we are getting late on planting corn. While the soil conditions are probably more important than planting date, there will be intense pressure on producers to plant corn this week. That means that some fields will likely get planted too wet. Getting into a field too soon is completely understandable given the logistics of planting multiple fields and trying to "sneak in" a field between rains.
If going into a field that is too wet, back off the down pressure and the closing wheel pressure. In addition, hope for some larger quantity of rains shortly after planting and before the soils dry. If the soils dry out immediately after a field was planted too wet, then sidewall compaction probably will occur in that field. Images of both sidewall compaction and surface compaction are included here to help you identify the problem about a month after planting.
Another common sign of compaction is nutrient deficiencies. Nutrient deficiencies develop because the root system has been limited within the compacted areas. Those confined roots can rapidly deplete nutrients in that area. Images of potassium deficient corn are below. Although tempting, foliar fertilization will not rescue the stands because the needs far exceed what can be applied economically in a foliar form.
Once compaction has occurred, whether sidewall or surface, there are no solutions for this season. The damage is done.
Written by Chad Lee and Carrie Knott, Extension Agronomists, University of Kentucky
