What is the definition of drift?

• A. The pesticide moves off target (even though it may have been properly applied)
• B. A pesticide mix is incorrect and mistakenly applied
• C. A pesticide changes from a solid state to a gas or vapor form
• D. A pesticide adheres to the target

Answer: (A)

Drift is the off-target movement of a pesticide through the air during application or shortly afterward, carried by air currents to areas not intended. The correct description fits this idea by saying the pesticide can move off target even when the application itself is done properly, highlighting that drift is about unintended transport, not an error in mixing or applying. It’s not about an incorrect pesticide mix, which is a formulation issue; it’s not about volatilization, which is a liquid turning into vapor; and it’s not about the pesticide sticking to the target, which would be proper deposition. In practice, drift depends on droplet size, nozzle and pressure settings, equipment speed, wind conditions, and temperature effects, and can be reduced by using larger droplets, tuning application parameters, avoiding windy conditions, and following label-recommended drift reduction practices.