Now, if I catch him again, without asking me, I will go ballistic. I think it wasn't his first time. One day last week I saw a bunch of bubbles on the surface in various places, like something had been dragged along the bottom, like a net.

No fences. I don't want to have to mow around a fence, and it would interfere a lot with hay operations, where you need to make wide turns.

No signs. You don't have to have them in this state. Trespassing of that type is obvious. There is no place to put purple paint, other than putting up posts that would become obstacles.