Seasonal Distribution of the Lesser Peachtree Borer 1 in Central Georgia 2 as Monitored by Pupal Skin Counts and Pheromone Trapping Techniques

Abstract

Seasonal distribution of the lesser peachtree borer, Synanthedon pictipes (Grote and Robinson), was monitored from 1967–1975 in central Georgia by counting the pupal skins found on trees and by recording male captures in sticky traps baited with synthetic pheromone in peach orchards. Counts of pupal skins on selected trees in the same orchard over 3 yr revealed that the population of borers increased substantially between 1967 and 1970, even though insecticides were being used. Insecticides, however, were not directed towards lesser peachtree borers but to fruit insect pests. Orchards with both high and low populations could be indexed by using the pupal skin counts and the captures of males in traps baited with synthetic pheromone. However, only high populations provided adequate data to confirm 2 peaks of adult eclosion with either sampling method. The spring (1st) peak always occurred in May; a 2nd peak was usually evident in August or September. However, a 2nd peak occurred in late July (1974) at Zenith, Georgia, and there were indications of a third peak during September. In this same orchard, captures of males in sticky traps baited with synthetic pheromone were very similar to the eclosion pattern made from pupal skin counts.