Entomopathogenic nematodes, Steinernema riobravis Cabanillas, Poinar and Raulston, were released at a rate of 2.6 billion/acre in a cotton field by gradually pumping a nematode slurry through a polyvinyl chloride pipe manifold into furrow irrigation water. Pink bollworm, Pectinophora gossypiella (Saunders) (PBW), were buried in wire baskets at 4 soil depths and on the middle and top of row beds. Percent PBW mortalities on Day 0, 14 and 39 following nematode treatment showed that S. riobravis moved 6 inches downward into the furrow and upward into the top of the row bed to find host PBW larvae. Overall mean percent PBW mortalities were significantly higher for larvae buried at 1/2 (33.7%) and 2 (35.8%) inches below the surface than for larvae buried at 4 (24.3%) and 6 (11.5%) inches below the surface. Larvae buried in the middle of the row bed had significantly higher percent mortalities (34.6%) than those buried at the top (11.3%) of the row bed. In all cases, overall mean percent PBW mortalities were significantly higher at Day 0 than at Day 14 and Day 39.