As indicated previously in the charts for methyl bromide and Telone II, coarse textured soils (those having a high percentage of sand) can be successfully fumigated at a lower rate than fine textured soils which have a high percentage of silt and clay. This is related to the size of the pore spaces associated with the different size soil particles. Fumigants move more rapidly through larger than smaller pores. In general, most nematicides can be moved more successfully (and so appear more efficacious) in coarse than in fine textured soils.