Pheromone traps were used to assess the distribution of two pheromone races of European corn borer, Ostrinia nubilalis (Hübner), in North Carolina, ≈10 and 20 yr after previous, similar assessments. In the previous studies, moths responding to a 97Z: 3E isomeric blend (Z blend) of 11-tetradecenyl acetate predominated in the far western parts of the state, whereas moths responding to a 3Z: 97E blend (E blend) prevailed in the east, with a substantial zone of overlap occurring in the eastern Piedmont. There was evidence that the E responsive population had expanded westward between 1978 and 1988. In this study, the distribution of the two races seemed to remain essentially unchanged from that observed in the late 1980s, and no evidence of a continued westward expansion of E responsive moths was detected.