Symptoms
Are you seeing uneven corn emergence in your field? Uneven corn emergence is most commonly caused by variable soil moisture levels, cloddy seed beds, uneven soil temperatures, variable soil crusting, herbicide injury, insect or disease damage, or replanting damaged fields by "filling in" rather than tearing down and starting over.
Summary
The following recommendations can help minimize uneven emergence:
Solution Steps
Tilling Wet Soils
This often creates cloddy seedbeds, a major cause of uneven stands. Reduce tillage trips in wet conditions.
Seed Depth
Check during planting in several areas of the field. Increasing seed depth as little as 1/2-inch can often eliminate most problems when seed-zone soil moisture is marginal.
Contact Between Seed and Soil
If it is poor or seeding depth isn't uniform, adjust seed openers/and/or closing wheel pressure. A change in secondary tillage operations may improve soil conditions for more uniform planting.
Surface Crop Residue
Under these conditions, adjust harvest, tillage, and planting equipment so residue cover over the row area is distributed uniformly after planting. If planting early in the season, remove heavy reside to help warm the soil.
Herbicide
Use recommended herbicide application rates to avoid injury to the corn.
After Planting
Closely monitor corn emergence and use a rotary hoe if a soil crust prevents uniform corn emergence.
Consistent Down Force Pressure
This is necessary in uneven field conditions to achieve uniform planting depth and is especially true in reduced till or no-till planting conditions.
