Seasonal Occurrence and Management of Grasshoppers (Orthoptera: Acrididae) and Katydids (Orthoptera: Tettigoniidae) in Leafy Greens Prior to Harvest

Hard-bodied orthopteran adults, in particular Acrididae, are an important source of insect contaminants in mechanically harvested leafy greens, Brassica spp. Because contaminants are usually detected after greens are fully processed, rejection of these value-added loads can be economically severe. A survey was conducted to determine the level of orthopteran species occurring in and around leafy greens fields prior to mechanical harvesting. This survey demonstrated that the vast majority of individual Orthoptera occurred around the edges of the field prior to harvest. In the second year of the survey, growers were already applying Sevin XLR^™ (Aventis CropScience, Research Trangle Park, NC) insecticide to grassy border areas in order to prevent acridid adults from moving into the field before harvest. The main taxonomic groups in Orthoptera found in this survey included Orchelimum sp. (Tettigonidae) (68.8%), Melanoplinae (Acrididae) (18.5%), other Acrididae (5.4%), Schistocerca americana (Drury) (Acrididae) (3.4%), Dissosteira Carolina (Linnaeus) (Acrididae) (2.4%), and other Tettigonidae (1.6%). Insecticide treatment of border areas prior to harvest provided a 94% reduction in Acrididae in the field prior to harvest.