What should a pilot do to minimize off-target movement of spray during a temperature inversion?

Delaying the application is the best approach to minimize off-target movement of spray during a temperature inversion because inversions create stable air conditions that can trap pesticide vapors and droplets near the ground. During an inversion, temperature increases with altitude rather than decreasing, which can prevent the normal mixing of air and cause spray particles to drift away from the intended target due to light winds or thermal turbulence.

Postponing the application until conditions are more favorable—such as when temperatures increase and air mixing occurs—allows for better dispersal of the spray, ensuring it stays within the targeted area. This helps mitigate the risks associated with pesticide drift, protecting nearby plants, water sources, and communities.

Other choices, such as increasing spray pressure or changing the spray pattern, may not effectively address the challenges posed by a temperature inversion and might even exacerbate drift issues. Flying at a lower altitude may seem beneficial but can lead to a higher risk of off-target movement due to the stable air layer created by the inversion.