In lraq, treatment of producing citrus trees with a 75% emulsifiable formulation of 1,2-dibromo-3-chloropropane (DBCP), applied in irrigation water at rates of 66-88 kg (a.i.)/hectare, gave excellent control of the citrus nematode (Tylenchulus semipenetrans) greatly improved tree vigor, and increased the fruit yield for at least 3 years after treatment. Applications made during the spring gave much better results than those made in the fall.