Which are factors that influence drift?

• A. Wind speed
• B. Wind Direction
• C. Temperature and Humidity
• D. All of the above

Answer: (D)

Drift is the movement of pesticide droplets away from the intended target during or after application. Wind speed influences how far droplets can travel—the faster the wind, the farther the drift plume can be carried. Wind direction determines where that drift goes, always downwind from the application site. Temperature and humidity affect how droplets behave after release: higher temperatures and lower humidity promote faster evaporation of smaller droplets, creating finer particles that stay airborne longer and drift farther; humidity can slow evaporation and reduce drift potential. Since each of these factors changes the distance and direction droplets move, all of the listed factors influence drift. So the best answer is all of the above.