Really? Good to know---learn something new every day!
I was thinking more along the lines of several 4×8 sheets of plywood backed by enough sheets of styrofoam insulation to float just above water level with an anchor on each end and after dumping a pile of corn on them. Three at most on one of those ponds would do the trick but that might be a little more obvious than the aforementioned method.
People always talk about being careful of planes but from what I've seen that only is an issue if you had them out less than a week before deer season when the DNR starts flying and looking for bait piles next to stands and in the woods. No one baits in MN so they're not even looking for it. Like with everything else the highest likelihood of being caught is by another hunter stumbling on your shyte and calling it in.
But that wouldn't be an issue at this place. What'd I pay just went up....I'm getting some ideas.