Trap Height Affects Capture of the Pecan Nut Casebearer (Lepidoptera: Pyralidae)1

Abstract

Abstract The pecan nut casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae), is a monophagous pest attacking pecan, Carya illinoinensis (Wangenh.) Koch. Pheromone traps attractive to adult males are used to monitor this pest in orchards by placing them in the lower canopy. However, some insects exhibit vertical stratification in tree canopies as does occur for some beneficial and pest species associated with pecan. The objective of this study was to assess vertical stratification of the pecan nut casebearer in the canopy of tall pecan trees when sampling with pheromone traps. Traps were placed at three heights in orchards (1.5, 7.6, and 13.7 m) above ground. In one experiment, only one trap was placed at one of the three heights at a tree. In the other experiment, three traps, one at each height, were placed in the canopy of the same tree. Results from both experiments reveal that the pecan nut casebearer does stratify within the pecan canopy. Significantly more moths were captured in the highest trap than in the traps at the other heights. These results provide information useful for developing pecan nut casebearer management strategies such as mating disruption in pecan orchards with tall trees.