The northern areas of the state usually do not have nematodes that persist from season to season. To determine if you might be affected, draw a line from east to west halfway from the Nebraska to the Oklahoma border. If you are located north of that line, don't worry about nematodes.
Nematodes are microscopic, wormlike animals that can seriously damage the roots of crop plants.
Certain soil-inhabiting nematodes are harmful because they feed on the roots of many kinds of vegetable and flower crops causing roots to become stunted and deformed. As a result, roots are less able to absorb water and minerals necessary for vigorous plant growth, and crop production is significantly reduced. Under severe nematode infestations, it is not uncommon for affected plants to die during periods of heat stress. Suspect a nematode problem if an unusual number of plants die during hot, dry summer weather. To verify this, dig up one of the affected plants and examine the roots.