Insecticidal management and movement of the brown stink bug, Euschistus servus, in corn

In eastern North Carolina, some brown stink bugs, Euschistus servus (Say) (Hemiptera: Pentatomidae) are suspected to pass the F(1) generation in wheat (Triticum aestivum L.) (Poales: Poaceae) before moving into corn (Zea mays L.) (Poales: Poaceae). These pests can injure corn ears as they develop. To test their effectiveness as a management tactic, pyrethroids were aerially applied to field corn in two experiments, one with 0.77 ha plots and another with 85 ha plots. Euschistus servus population abundance was monitored over time in both experiments and yield was assessed in the larger of the two experiments. In the smaller experiment, the populations were spatially monitored in a 6.3 ha area of corn adjacent to a recently harvested wheat field (352 sampling points of 6.1 row-meters in all but the first sampling event). Overall E. servus abundance decreased throughout the monitoring period in the sampling area of the smaller experiment, but remained unchanged over time in the large-scale experiment. During all sampling periods in both experiments, abundance was the same between treatments. Yield was unaffected by treatment where it was measured in the larger experiment. In the smaller experiment, E. servus were initially aggregated at the field edge of the corn (two, six and 13 days following the wheat harvest). Sixteen days following the wheat harvest they were randomly distributed in the corn. Although it was not directly measured, stink bugs are suspected to move the cornfield edge as a result of the adjacent wheat harvest. More study of the biology of E. servus is needed, specifically in the area of host preference, phenology and movement to explain these phenomena and to produce better management strategies for these pests.