Absence of growing plants, achieved by clean fallow or flooding, can reduce nematode populations. However, flooding for two to three months may be impractical, and clean fallow may result in soil erosion. Organic Amendments . It is difficult to predict how organic amendments, such as compost, crop residues, yard waste, manure, or other biosolids, might affect nematode populations. Although some decomposition products have been shown to affect nematodes in the laboratory, performance under field conditions has been inconsistent.
Any organic amendment is a potential source of nitrogen that can stimulate plant growth.
In some cases, increased root growth may even result in increased nematode populations. Interpretation of results from organic amendment applications can be difficult, since the fertilizer effect may stimulate plant growth, while effects on nematode populations may be unclear or unknown. High temperatures will kill nematodes, and so steam sterilization or other forms of heat treatment are often used for sterilizing soil used in greenhouses or nurseries. Soil solarization is receiving increased attention for the management of nematodes and other soilborne pests. In this method, a thin sheet or tarp of clear plastic is placed over the soil surface, allowing the sun to heat the uppermost layers of soil.