If you want to stop trespassing on your land, lease the rights to a hunter. They will do everything in their power to keep anyone else off the property. My father has used this tactic for years and it has worked like a charm. The hunter gets to hunt and basically you know exactly who is on the property and they keep everyone else off.
Back to hunting for a moment (bear with me, I'll get there).
When I was a kid we barely ever saw a deer in our county. Now my parents report seeing them on a daily basis. In 2006 I was in the local DOT office and they had a running count of the number of deer they had picket up on the highway. At that time the population of the county was less than 30,000 people and they had picked up almost 500 deer who lost a battle with a car. That does not count all those the people hit and took with them. That is one county out of 100 so assuming even half that number are picked up in other counties that would be 25,000 deer hit by cars in NC per year. The DOT put out a press release in 2011 indicating 20K+ animal/car interactions so I'm not far off.
For the 2013-2014 NC deer season the harvest was 153,629. Now if you look at 1976, when we hardly saw a deer, the harvest numbers were 123,312. The point being the deer numbers in NC are growing at a much faster rate then the harvest and we actually need more hunters to manage the population. I saw four the other night coming home in a developed area which could have caused some major injuries had they ran into traffic since the road was two lanes in either direction with no shoulders and narrow lanes. We actually need more people to hunt to reduce the number of accidents. (Full disclosure - I don't hunt, I don't like cleaning the animal.)
Hope you find a solution to keep unwanted people off your property, but I suggest you secure a hunter and let them do it for you.