Temporal, spatial, and vertical distribution of plum curculio (Coleoptera: Curculionidae) in southeastern peach orchards.

Plum curculio (PC), Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), is a key pest of Southeastern US peaches. To facilitate the development of spatiotemporally targeted management approaches and improve the deployment and design of monitoring traps, we studied PC's vertical distribution within peach orchards and whether their dispersal patterns resulted in an orchard edge effect. Non-baited Whalon-modified Tedder's traps (black pyramid traps; ∼120 cm in height) deployed at 3 heights-0 (low), 120 (medium), and 240 (high) cm above the ground-revealed that PC were captured at all heights but predominantly in the low traps. Additionally, correlations among PC captures at different heights were often nonsignificant. Although we documented the presence of PC's edge effects in Georgia peaches for the first time, the occurrence of these effects was inconsistent across 2 yr, failing to regularly appear early in the season when PC entered the orchard from overwintering sites and late in the season when they departed to seek overwintering sites. Overall, our findings suggest that relying solely on ground-deployed pyramid traps for PC monitoring may not accurately reflect overall PC abundance in the field. Unlike in Northeastern apples, where PC consistently exhibits an edge effect, targeted management programs that focus insecticide applications on PC in perimeter tree rows rather than the entire orchard are not currently recommended for Southeastern peach production systems.