California Agriculture

Effective ant control is critical for controlling honeydew-secreting homopteran agricultural pests such as whitefly and mealybug. Low-toxicity ant baits may more effectively control ants than the broad-spectrum insecticides currently used in California vineyards and citrus orchards. This study focused on developing effective ant baits for use in bait stations to control field ant and Argentine ant, which aggressively tend homopteran pests. In the Coachella Valley, field ant is associated with the vine mealybug, a destructive nonnative pest. We conducted preference experiments for various commercially available ant baits and a bait formulated with anchovy plus imidacloprid. Field ant preferred the anchovy baits above all others tested, and in field trials the anchovy bait with 0.005% imidacloprid significantly reduced foraging activity. Argentine ant is the primary ant pest in vineyards and citrus orchards of California’s nondesert growing regions. We tested the efficacy of several chemical bait treatments, all of which significantly lowered Argentine ant populations.