What is the best practice to reduce physical spray drift during herbicide application?

Spraying when wind speeds are low is indeed a best practice to minimize physical spray drift during herbicide application. Wind can carry small droplets of the herbicide away from the target area, reducing efficacy and potentially causing harm to non-target plants and the environment. Low wind speeds help ensure that the particles stay more directly over the intended application site, leading to better control of where the herbicide lands and reducing the risk of drift.

While spraying at high humidity levels can help droplets stay intact and reduce evaporation, it does not directly control drift as effectively as low wind speeds do. Using larger droplet sizes is beneficial as well because larger droplets are less likely to be affected by wind, but wind conditions have a more immediate impact. Lastly, applying during cloudy weather may contribute to a reduction in evaporation but does not necessarily mitigate the effects of wind on drift. Therefore, the practice of spraying in low wind conditions stands out as the most effective measure for controlling physical spray drift.