What two factors should pesticide applicators be most aware of to avoid vapor drift?

The correct factors that pesticide applicators should be most aware of to avoid vapor drift are droplet size and wind speed. Understanding these elements is crucial because they directly influence how pesticides are applied and their potential movement off-target.

Droplet size affects how particles behave in the air. Smaller droplets can remain airborne for longer periods and may travel further due to wind, which increases the risk of drift. Larger droplets are less likely to drift because they fall to the ground more quickly. Thus, selecting the appropriate droplet size helps minimize the potential for unwanted pesticide movement.

Wind speed plays a significant role in drift risk as well. Higher wind speeds can carry aerosolized droplets or vapors over longer distances, which may lead to deposition on unintended areas beyond the application site. Therefore, applicators need to monitor weather conditions and choose suitable times and methods for pesticide application to mitigate drift risks.

While temperature and pesticide volatility are important considerations, they primarily relate to evaporation and the potential for substances to enter the air as vapors. Humidity and temperature can impact evaporation rates but are not as critical as droplet size and wind speed in controlling vapor drift. Soil composition and water table depth pertain more to pesticide interactions with the soil rather than airborne drift concerns.