What presents the most likely risk of contaminating a neighbor's property after outdoor pesticide application?

Drift is the most likely risk of contaminating a neighbor's property after outdoor pesticide application because it refers to the movement of pesticide particles or droplets away from the target area through the air. This can occur due to factors like wind, temperature inversions, or even simple evaporation. When pesticides are sprayed, they can be carried away from the intended application site, potentially landing on neighboring properties, which poses a significant risk to non-target plants, animals, and humans.

This aspect of drift highlights the importance of proper application techniques, timing, and environmental conditions to minimize the risk of unintended exposure to neighboring areas. Ensuring that the application equipment is calibrated and using protective barriers can also help limit drift, ultimately safeguarding adjacent properties and ecosystems.