The best sampling time actually depends on the purpose of the sampling. If detection is the purpose, soybean cyst nematodes (SCN) can be sampled throughout the year. The ideal time would be following harvest when nematode levels are likely to be highest. Concentrate on areas of the field where yields were less than expected and sample directly within the row since SCN is most likely to be in the root zone. If the purpose of the sampling is to determine current levels in known infested fields for management purposes, late fall or spring would be optimal times. In northern climates, fall or early spring is ideal since nematode levels decline very slowly through the winter. In more southern climates, spring time, just prior to planting, is best since nematode numbers often fall dramatically through the winter in the warmer southern soils. The following link gives more detail on sampling for SCN. Plant Health Initiative www.planthealth.info/scn_scout_nextyear.htm

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