What are common causes of off-target pesticide injury?

The correct answer identifies drift and volatilization as common causes of off-target pesticide injury. Drift refers to the movement of pesticide droplets away from the intended application area, often due to wind, leading to unintended exposure of non-target plants or organisms. Volatilization involves the transformation of pesticides into vapor, which can also disperse over distances from the application site, allowing them to settle on unintended targets. Both processes highlight the significance of environmental conditions and the physical properties of pesticides in determining their impact beyond the intended area.

In contrast, while over-application and improper calibration can lead to excessive pesticide being applied, which may increase the likelihood of injury to sensitive areas, these factors don't inherently cause off-target movement in the same way that drift and volatilization do. Similarly, applying pesticides near sensitive plants indeed poses a risk, but it does not address the mechanisms through which pesticides move away from their target. Lastly, using expired products can lead to decreased efficacy or altered effectiveness but is not a direct cause of off-target injury in terms of dispersion. Thus, drift and volatilization are key factors that specifically contribute to off-target pesticide injuries.