Targeted herbicide spraying systems: role of nozzle type, number of nozzle activation, nozzle orientation, and boom height on spray coverage and weed control

BACKGROUND: Differences in ground-based sprayer setup within targeted herbicide application systems can influence spray coverage and herbicide efficacy. This research aimed to improve understanding of how these factors affect spray coverage and weed control using complementary field and controlled-environment experiments. RESULTS: ), TP40015E and DG80015 nozzles produced similar spray coverage (25%). A 53 cm boom height provided greater spray coverage under both no-wind (52%) and wind (32%) conditions compared to 76 cm (41% no-wind versus 18% with wind; Study 2). Multiple-nozzle activation resulted in higher spray coverage than a single-nozzle activation under no-wind (58% versus 36%) and wind (29% versus 19%) conditions. Multiple nozzles also resulted in greater weed control (> 92%) and biomass reduction (95%) than single-nozzle activation (78% control and 87% biomass reduction; Study 3). Under no-wind conditions, conventional 0° and 30° rearward inclined nozzle orientations provided comparable spray coverage (≥ 42%) and did not differ in weed control or biomass reduction. In contrast, under wind conditions, the 30° rearward inclined orientation resulted in the lowest spray coverage (16%; Study 5). CONCLUSION: Regardless of boom height, nozzle orientation, and wind, activation of multiple nozzles resulted in better spray coverage and weed control than single nozzle activation. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.