Clear skies and sunshine don't necessarily mean soil conditions are fit for planting. If you question whether areas of a field are dry enough to enter, do a quick test, suggests Nick Benson, corn product specialist at Latham Hi-Tech Seeds. Roll some soil into a ball in your hand. Observe whether the soil breaks apart as you work it.
With the record-setting amount of rainfall received across the state this spring, and a race against time to get the 2013 crop in the ground, it's likely that many seeds were "mudded in." Some easy ways to identify if your field is impacted by soil compaction is by looking for slow water infiltration, water ponding, increased runoff and erosion following an ordinary rain, he says. Nutrient deficiencies in soil can also be attributed to soil compaction. Poor root development and stunted plant growth caused by inadequate nutrients can also help identify an area being affected by soil compaction.
This link will take you to a youtube video featuring Benson actually demonstrating one of the soil condition tests discussed in this article.
Heavy rains and wet soil this spring did more harm than just delay planting
For all of these reasons, Iowa State University research shows compacted fields may experience yield losses of 10% to 30%. That's why it's important to try and manage the situation as best as possible in future years. Tillage may help water infiltrate the soil rather than sitting on the surface. It also may help increase air movement and improve root growth.
Keep in mind, however, that deep tillage is detrimental to soil organisms like nightcrawlers that need crop residue and to soil fungi that help improve soil structure. To help remediate soils, agronomists suggest you plant a cover crop with vigorous roots. Manure and compost also can help improve surface soil structure.