X-ray Computed Tomography Studies of the Burrowing Behavior of Fourth-Instar Pecan Weevil (Coleoptera: Curculionidae)

Abstract

X-ray computed tomography (CT) was used to study the burrowing activity of fourth-ins tar pecan weevils, Curculio caryae (Horn), and soil structure in soil cores. X-ray CT clearly showed tunnels of the burrowing larvae and revealed that, following their exit from infested nuts, the fourth instars burrow vertically into soil cores to mean depths of 67-92 mm in Cecil, Tifton, and Lakeland series soils. Hardpans of 1.6-1.8 Mg/m3 were penetrated by the larvae, although more dense objects (e.g., rocks) limited vertical movement.