Population estimation via pheromone traps and establishment of a damage threshold for the Nantucket pine tip moth, Rhyacionia frustrana (Comstock) (Lepidoptera: Tortricidae), in the Georgia Piedmont

Pheromone traps baited with synthetic baits are used in southeastern pine plantations to monitor the phenology of the Nantucket pine tip moth, Rhyacionia frustrana (Comstock), for timing of insecticide applications. Methods were developed to utilize these traps for predicting future population density and damage by this pest. Trap catch was strongly correlated with tip moth population density and damage within generations. Additionally, trap catch of overwintering moths was a strong predictor of tip moth damage during the subsequent generation.; Trap catches of tip moths have been difficult to interpret because they decrease considerably relative to population density from the spring through subsequent generations. Understanding this pattern is important for optimizing trap usage and catch interpretation. Two hypotheses were tested to explain this phenomenon: (1) there is decreased efficacy of synthetic baits during summer due to greater or unequal volatility of pheromone components or increased competition for males by calling females and (2) decreased adult longevity during summer. The latter hypothesis was confirmed and suggested as the primary reason for low catches in hot weather.; Studies were conducted to determine a damage threshold for Nantucket pine tip moth to assist forest managers with implementing pest control options. Low but persistent tip moth populations over three years resulted in significant wood volume losses, and regression models were used to estimate long-term impact. An average damage threshold of 10–20% of infested shoots per whole tree was found for the first three years following plantation establishment.; In an additional study, the volatile profile of slash pine and associated tip moth damage levels were compared during each of four tip moth generations in the Georgia coastal plain. This study was undertaken to establish a basis for increased resistance to tip moth manifested by slash pine as newly planted seedlings become established during their first growing season. Understanding the nature of slash pine resistance to tip moth may provide clues on how to increase resistance in loblolly pine, a much more susceptible host.