Which factor has no effect on off-target pesticide drift?

A constant 3 mph wind has no effect on off-target pesticide drift because it represents a consistent and stable airflow condition. When wind speed is constant, it can actually be easier to predict and manage the drift of pesticides during aerial application. Drift typically occurs due to variable conditions that change unpredictable, such as fluctuations in wind speed, direction, and atmospheric stability.

In contrast, factors such as variable humidity, temperature changes, and wind gust variability all introduce unpredictability into the application environment. For instance, variable humidity may alter the evaporation rate of the pesticide and affect droplet size, while temperature changes can influence the volatility of the pesticide. Wind gust variability can create sudden changes in the direction and strength of wind, which may carry pesticide droplets away from the intended area more easily. Therefore, a constant wind speed does not contribute to off-target drift in the same way that these other factors do.