Weather Factors Influencing Capture of Cydia pomonella (Lepidoptera: Tortricidae) in Pheromone Traps During Overwintering Flight in California

Capture of male codling moth, Cydia pomonella (L.), with pheromone-baited sticky traps in an orchard in Kern County, Calif., during 1983–1988 was associated with air temperature, relative humidity, wind speed, wind direction, vapor pressure, dew point temperature, and rainfall. Based on a stepwise logistic regression analysis, mean evening air temperature, wind speed, and vapor pressure significantly affected the probability of moth capture. All moths were captured on dates whose mean evening air temperature was > 12.01°C, wind speed was <3.62 m/s, and rainfall was <0.375 mm/h. Evening temperatures >15.8°C (21.1°C maximum daily) were associated with consistent observations of male flight as measured by pheromone traps. Knowledge of weather factors affecting moth capture in pheromone traps could help in interpreting trap catch data and may lead to fewer treatment decision errors.