Which factor does NOT affect spray droplet size during aerial application?

The factor that does not influence spray droplet size during aerial application is the color of the liquid. Spray droplet size is primarily determined by physical and mechanical characteristics such as nozzle type, which affects the formation of droplets, wind speed, which can cause droplets to break up or drift, and spray pressure, which influences the velocity and distribution of the droplets as they exit the nozzle.

Color does not alter these physical properties; rather, it is a characteristic related to the chemical composition and formulation of the spray material which does not impact how those particles are formed or their subsequent behavior in the air. Therefore, while factors like nozzle design, wind, and pressure are critical for ensuring optimal droplet size for effective pest control, the color of the liquid is irrelevant in this context.