Male and female codling moth, Cydia pomonella (L.), weremonitored with passive interception traps (PI-traps) in apple orchardstreated with sex pheromone dispensers. The proportion of mated femalesrecaptured by PI-traps was significantly higher than the proportionreleased after the release of both sexes into a codling moth-infestedorchard. However, no significant difference occurred between theproportion of mated females recaptured and released when only femaleswere released into uninfested orchards. Replicated nine-tree appleplots situated either on the edge or in the center of pheromone-treatedapple orchards were monitored with PI-traps during first moth flight in1995 and during both flights in 1996. Moths caught on PI-traps werepredominately males. The first male moths were captured 7–10 d beforefemales during the first flight in both years. Initial capture ofvirgin and mated females on PI-traps coincided in 1995. Mated femaleswere captured 14 d after the first virgin females in 1996. Themean proportion of females that were mated ranged from 32 to 55%during the first flight and 85 to 92% during the second flight. Mothcatch and fruit injury were significantly higher in the edge versus thecenter plots. The numbers of total and female moths caught withPI-traps were significantly correlated with fruit injury for eachgeneration. The percentage of female moths caught on PI-traps that weremated was 32% lower and the mean oocyte load of all females was 42%higher in a pheromone-treated apple orchard than in the untreatedcrabapple grove monitored during May and June 1997.