Because insect pests are a major limiting factor to producing profitable soybeans in South Carolina, and our treatment thresholds for controlling those pests are in need of refinement, we propose to simulate defoliation and stem injury to plots and correlate with yield impacts. While conducting these trials with artificial injury, we will also run similar opportunistic trials with natural populations of insects, as available.
Because stem feeders, such as threecornered alfalfa hopper (TCAH), lesser cornstalk borer (LCB), Dectes stem borer, and other species, can reduce stands and yields, we propose to target selected fields with a high probability of developing problems (e.g. planted into cover crop with late burndown) and evaluate treatment thresholds with natural populations. We also propose to simulate stem-feeding injury in soybeans with two methods: 1) hand thinning of stands with scissors or shears and 2) selective elimination of plants with herbicides.