If nematodes are present, distribution is generally patchy in a field. Generally, summer or late fall is recommended. Populations are usually low in spring and build through the growing season to reach peak densities at harvest. Samples should be taken before cultivation when rows are still in place.
Populations concentrate around existing root zones.
Costs are based on the number of samples collected, analyzed, and evaluated. The greater the number of samples collected, the more accurate and reliable the estimate will be. The cost of an accurate population assessment should not exceed the cost of nematode management and the benefits of control. Review previous cropping patterns. Assess soil texture and changes in the field.