We bought a hair under 70 acres of vacant land in 2010 that was a part of a larger parcel that totaled about 100 acres. At the time of our purchase, the former owner hadn't set foot on the property in over 15 years so the locals treated it as community property. We had permission to use the property between the time when our offer was accepted and the closing. Just to give you an idea on how many people were using the parcel, EVERY SINGLE TIME we visited, we ran into someone.
My wife would get pretty steamed when we ran into people and wanted to be a tad hostile but we agreed to treat them all in a very friendly manner, especially since we lived 20 miles away (I didn't want to make an enemy who sought some sort of juvenile revenge on our equipment when we weren't around). It's funny, nearly everyone we bumped into said they had permission from the previous owner to be on it.
My approach to handling these situations was this: I was very friendly whenever I met someone. After all, I was meeting one of my neighbors. I would mention that I've never told anyone they can't be on the property but that they need to call me to see if it's ok before venturing onto the property. I further mentioned that I planned on doing a lot of hunting and target shooting and wanted to make sure no one was around before we started shooting. I then asked them if they'd like me cell number. If I gave them mine, I made sure to get theirs. I also tried to do some shooting here and there when we were working on the property. I made it a point to have a big shooting party annually for the first two years we owned it. I had about 15 guys come down for a few hours of shooting. The cops even made the party both times.
I think my approach really worked for 98% of the people who had been using the property. I was nice so they didn't have any excuse to get back at me; they were probably a bit nervous about the shooting going on and didn't want to venture into the firing range; when I introduced myself they had to do the same so they were no longer anonymously trespassing. I think just being physically present was very helpful too.
I've found my neighbors to be very helpful in dealing with some problems we've had over the years. I think if I'd have taken a hard line when we first met, despite them being in the wrong many times, I'd feel a lot more paranoid about them today. Most of the ones I know have become friendly acquaintances and actually look out for the areas of the parcel that I can't readily handle myself.
By the way, most people declined to take my number but were friendly to me and said they just wouldn't use the property any more. I've only received a couple of calls over the years from those wanting to use the property.
