Seasonal movement patterns of Halyomorpha halys Stål (Hemiptera: Pentatomidae) nymphs on wild and tree fruit hosts at the orchard-woodland interface

The invasive and highly polyphagous brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae) has become a serious tree fruit pest in the mid-Atlantic region of the US and caused dramatic changes to orchard pest management practices.  H. halys nymphs and adults feed on and injure tree fruit. Nymphs are capable of walking considerable distances and their fitness is optimized when they develop on a mixed diet. Mid-Atlantic fruit orchards are often bordered on one or more sides by woods comprised of deciduous tree species on which large H. halys populations can develop. The objective of this study was to monitor season-long patterns of nymphal movement on to and off of wild and tree fruit hosts at the orchard-woodland interface using trunk traps. Traps that passively intercept nymphs walking down and up tree trunks were installed on apple (3 sites) and peach (2 sites) trees at orchard borders adjacent to woods. At each site, traps were also installed on tree of heaven, Ailanthus altissima (Mill.) Swingle and other wild hosts at the woods edge. “Up” and “down” traps were installed on individual trees of each host (n = 5 pairs of each host/site). Captures were recorded weekly from mid-May to mid-October, 2014 and compared among the wild and tree fruit hosts across the growing season. Understanding the seasonal movement patterns of H. halys nymphs among their known hosts can provide predictive information on host-use activity, potentially aiding development of temporally precise and ecologically sound orchard pest management programs.