Our 1/2 acre pond in upstate NY is getting overrun with watershield. We tried to control it by manually removing in July. That was an arduous task and it only lasted about 2 weeks. I've resigned myself to the fact that we need an herbicide.
What is best to use and who can I get to do the application?
We are in Ulster County NY.

If you can't find anything on the web ( see https://aquaplant.tamu.edu/management-options/water-shield/ ).Contact Dr. Mark Cornwell, at SUNY Cobleskill. He is a great guy, a strong Pond Boss contributor, and probably knows NY state fish and fisheries better than anyone else.