This article discusses various factors that delay seedling or prevent emergence. The second article, Making a Replant Decision, discusses the factors involved in making a decision to replant a damaged stand of corn. Seedling emergence can be delayed or prevented by several factors. These include cool soil temperatures, cloddy soil, soil crusting, insects, diseases, and herbicide injury. Seeds that do germinate may emerge unevenly.
Uneven emergence can greatly reduce yield.
The resulting stand may emerge unevenly. Prolonged cool soil temperatures combined with wet soils may favor the development of soil pathogens that cause seed rot. In reduced-till systems under heavy crop residues, soil temperatures will be cooler at the seed depth. Germination will be slower and seedling establishment later. Cloddy soils and other tillage related problems caused by working soils that are too wet, result in poor soil to seed contact.