My son in law currently has a lawncare company and would like to incorporate organics into it. Are there license or cetifications required to advertise as being organic? What would be the best literature for him to read as a reference guide? I'm really the one that's pushing him to do this as I have always been organic and would not consider being otherwise.
Thanks for any information or guidance you can give me.

At this point there are no registration requirements by the state or by the feds that I know of. There will be a movement that direction but for now just advertise organic procedures and products and be honest with the customers about what you are doing. Try to avoid the red tape and fees as long as possible.