Large scale field experiments were conducted in 2006 and 2007 that evaluated the efficacy of Steinernema carpocapsae applied by chemigation. Most of the trials were conducted in unharvested pistachios and a single trial was conducted in almonds in 2007. The efficacy of the nematodes varied. The reduction in adult emergence ranged from 25-70%. It was easy to apply the nematodes and the best time appears to be in mid February. Efficacy data will be presented.