Potential overwintering refuge sites for kudzu bugs (Hemiptera: Plataspidae) and parasitoids.

The limited number of studies exploring stink bug egg parasitoid overwintering refuges and the discovery of invasive kudzu bugs Megacopta cribraria in North Carolina, prompted this study to explore the potential refuges that kudzu bugs and parasitoids might be utilizing during winter conditions in North Carolina. Three fields were selected in Clayton, (Johnston County, NC) which had soybean plantations in summer with high populations of stink bugs, along with a south-facing woodland border. Fine mesh cages (3 feet in height) with a funnel-bottle collection system at their tops were wrapped around boles near the base of paired, adjacent pine and sweet gum trees at each location in January 2013. Pines and sweet gums were chosen for sampling because of the number of potential refuge sites in their bark, and previous anecdotal observations. Insects that emerged in spring from tree bark were collected and identified. Throughout the 2012-2013 winter, leaf litter samples were collected from 1 sq. ft. areas adjacent to north and south sides of caged trees, as well as between paired trees. These litter samples were taken to a greenhouse for extraction using mesh bags with funnel-bottle collectors at the top. Results indicate presence of kudzu bugs (preferentially in the south-facing leaf litter at the base of trees), and parasitoids like scelionid wasps.