an age old problem brettski...IMHO, it aint gonna matter what you post, but you can feel good about saying what you feel the best way you know how.
this was discussed on an earlier thread (sorry i am not a thread master) involving wicked and some others....."half" jokingly, my favorite is "trespassers will be shot......survivors will be shot twice"
perhaps in addition to signage (which in CA you must have signs every 50 feet to hold up a liable court claim) you should have all your neighbors sign an indemnification clause (aka release of liability agreement).
our chosen signage states "private property, no trespassing, residents and invited guests only"
we also have a variety of smaller signs here and there stating no tresspassing, no hunting, no fishing, no poaching. people come down anyway, and i'm glad to be (mostly) working out of my house to keep an eye on things.