Soil was collected from cotton fields in Louisiana, Mississippi, and South Texas where the reniform nematode (Rotylenchulus reniformis) was present at much lower population densities than would be expected based on soil texture, cropping history, and infestation levels in nearby fields. Soil was mixed 1:10 or 1:20 with a fine sand supplemented with vermiculite and balanced nutrients, and placed within 0.5 liter pots that were planted to Upland cotton cv. Fibermax 832. Two weeks after planting, each pot was inoculated with 4,000 vermiform R. reniformis, and 7 weeks after inoculation, three cores were removed from each pot to evaluate nematode populations in pots. In some treatments, pots amended with field soil had nematode population densities 80% lower than in controls, indicating the possible presence of transferable suppressive agents.