The droplets would fall to the ground right away. They dont jump up into your nose after they have hit the ground. If a cropduster flew over then you would have to be standing in the spray and subsequently smell it to try and figure out what it was before you would get enough to cause infection.
Could it be something as simple as this old guy just likes to "wrestle" with sheep?
It's a fog. Yes it gets to the ground eventually. Dump it at high altitude, not low, and the carrier liquid evaporates, the solids are then like dust in the wind. There is no smell, or warning at all and the plane is miles away.