Nantucket pine tip moth phenology and timing of insecticide spray applications in seven Southeastern States
The Nantucket pine tip moth, Rhyacionia frustrana (Comstock) (Lepidoptera: Tortricidae), is a common pest of Christmas tree and pine plantations throughout much of the Eastern United States. The moth completes two to five generations annually, and insecticide spray timing models are currently available for controlling populations where three or four generations occur. The thermal requirements for the Nantucket pine tip moth to complete a generation were obtained from published data and used along with historical temperature data to produce maps indicating the number of annual generations predicted to occur throughout seven Southeastern States. Spray timing prediction values were also obtained from published data and used to predict optimal spray periods based on 5-day increments for each location where either three or four generations occurred. Approximately 80 percent of the predicted optimal spray periods were within one optimal spray period of previously field-determined spray dates. Land managers who use contact insecticides, such as synthetic pyrethroids, may find the predicted optimal spray periods useful in optimizing spray effectiveness.