Corn is a grass and has a fibrous type root system, as compared to soybeans or alfalfa which have tap root systems. Successful establishment of the corn plant's root system helps ensure successful establishment of the crop itself. Stunting or restriction of the root system, especially in young plants, will likely stunt the entire plant's development. To best understand rooting problems, it is important to understand that the corn plant actually establishes two distinct root phases, one more important than the other. This initial seminal root system anchors the young plant and absorbs water and nutrients for the first two to three weeks.
Seminal roots cease new growth shortly after the coleoptile emerges at the soil surface.
Within a few days after emergence of the coleoptile and first leaves from the soil, a second root system, the nodal roots, begin to develop from the crown or growing point. If damage occurs to seminal roots or the mesocotyl before nodal roots become established, stunting or death of the plant will occur. Such damage includes salt injury from excessive rates of starter fertilizer, seedling blight, herbicide injury and insect feeding damage. Root System Nodal roots begin to elongate from the coleoptile crown shortly after growth stage VE and are distinctly visible by growth stage V1. By growth stage V6, the nodal roots are the main root system of the plant.