1. You should avoid entering areas that have recently been sprayed with chemicals. Many times you will find flags or postings indicating that the area has been sprayed, usually in a public park, side of the road etc. Some of these chemicals are toxic to humans.
2. Each state uses a different system and laws to notify you of a potential spray that they are planning to do in your community in the near future.
3. You may be able to find some additional information at your local health department about potential spraying for mosquitoes. Take a look at your local newspaper to see if they are doing something major in your area.
4. Make sure to connect with friends and farmers to find out their spraying schedule and the type of pesticide they will be using/working with in advance.
You can always ask to speak to a pesticide specialist by calling the National Pesticide Information Center at 1-800-858-7378
Jose Lamas, University of Minnesota Extension