RE: Any Tips on how to keep others out of my ladder stands??
put a sign down near the bottom of the tree that says something to the effect of this:
"This stand and property is private and you are trespassing. You've been photographed with a concealed motion-detection camera. This photo will be used in your trespassing prosecution if you proceed with anything other than leaving now."
Don't even really have to have a camera. Just the thought of it may deter them from climbing up and using it.