Unless they were spraying city property, they should be paying to repair your grass. That is assuming you were keeping it mowed. Even then they would have to send you a notice before spraying.
Even if it is an easement, as long as it is still on your property and you are not obstructing their rights to the easement, they cannot destroy your property. They have to repair any damage they do while using your easement. I went through this once w a phone company and they had to repair my fence, replace my plants and fix all the ruts they left when driving through my yard. I picked up all their trash and cig butts and returned them to my local office along with a bill for the damage and photos. The manager was at my door the next morning and made the crew return to clean it up and he wrote me a check to replace the plants they destroyed.
