Experiments were conducted to evaluate the impact of spray volume, nozzle type, adjuvants, the presence of dew, and their interactions on foliar retention of creeping bentgrass. Tartrazine, a common food dye, was used as a tracer in this study. Increasing spray volume from 95 L ha^–1 to 1,500 L ha^–1 decreased foliar retention efficiency from 98% to approximately 85%. Compared with flat-fan nozzles, air-induction nozzles delivered similar retention efficiency at all spray volumes evaluated. However, flat-fan nozzles provided higher uniformity and more thorough coverage. Adding nonionic surfactants, organosilicone adjuvants, or methylated seed oils at typical concentrations yielded retention efficiency of approximately 90% to 93% regardless of spray volumes. In contrast, with water alone, increasing spray volume reduced retention efficiency from 95.9% to 87.3%. Simulated dew applied at 1,950 L ha^–1 increased retention efficiency by approximately 3% when spray application volume was 190 L ha^–1, while no difference was observed at 750 L ha^–1. The presence of dew reduced the impact of adjuvants on retention efficiency. Large quantities of dew, 3,800 L ha^–1, did reduce retention efficiency.

Nomenclature: Creeping bentgrass; Agrostis stolonifera L. AGSST ‘L93'