RE: To post or not in PA
I'd definitely recommend doing two of the things already mentioned. Post it, and make friends with neighbors.
As far as posting it goes try to get the signs that have a spot to write in your info if you want to let others hunt by permission. Ethical hunters will use the info to contact you and ask permission.
Your neighbors will be your best asset when you're not around. Posted or not folks will still trespass. Also, some wind as well as unethical hunters can make posted signs disappear. On the same note be sure to walk the property line every so often to make sure the signs are still there and no one has cut their way in.
Just my 2 cents. Dealing with the same thing myself in MA.
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