Final populations of Tylenchorhynchus agri Ferris were larger in Cisne silt-loam than in Dana silt-loam, Onarga fine-sandy-loam, and Sparta loamy-fine-sand which were planted to 'Kenland' red clover (Trifolium pratense L.) or left fallow for seven months. Populations of Helicotylenchus pseudorobustus (Steiner) Golden and Paratylenchus projectus Jenkins were smaller in soil inoculated with T. agri than in uninoculated soil, for some soil types and treatments. There was no difference between the growth of plants in soil inoculated and not inoculated with T agri.
