"Shell91" wrote in
:


I'm thinking seriously about digging a small trench and setting the
new fence in concrete. It might help although I've seen snakes
climbing trees around here.

I don't know enough about snakes to know if the aquatic kind can climb
walls, but it wouldn't surprise me if they can. But hopefully a solid
fence would make it less convenient for the snake (or snake's prey) to make
it's way into your yard. If the fence's color contrasts greatly with the
snake, the small ones, if they can climb the fence at all, should make easy
pickings for any predators (herons, hawks, giant bullfrogs) on the other
side.