You can't sue someone for negligence if you are committing a crime by trespassing.
It like a bank robber suing the guy that dropped a banana in the bank which resulted in the robber falling and breaking open his skull.
If you're trespassing and you are injured, the court would look at it like the injury would not happen if the trespassing did not happen first.
You can find plenty of stories where people put cables across trails on their own property to prevent trespassing on trails. Then a snowmobiler or ATVr or motorcycler comes through and gets decapitated. The cable hanger goes to jail, and gets sued, and loses.
No one has the right to trespass on that property. Not the OP, not Russell, not anyone. I can understand why the OP would want to clean up the property. And I can understand why the OP wanted to redirect traffic away from his own property. There is a woods behind our house that neighborhood kids turned into a BMX track. Seemed innocent enough... until they started stealing things out of everyones' yards to enhance their track, started hauling in furniture, starting campfires, leaving trash, drinking, night parties, cutting through our yards to get to the track, etc... it was a complete nuisance. So I contacted the land owner and the police. We worked together to get the police to confront the trespassing kids and eventually the problem cleared up.
Another example is our remote tree farm. When we bought it, there were dirt bike trails all over it. My first inclination was to block off all the trails. I consulted my insurance agent. He advised against it for the reason that the trails were open for an unknown amount of time. People were used to using them. Abruptly blocking them off could lead to someone unexpectedly running into an obstruction and getting injured. Even though they were trespassing, they would have had a reasonable expectation that the trail they had been using for X years was open, and most likely, they'd sue for damages. He said I'd lose in court and the insurance company would have to pay out. So here's how he suggested to deal with it.
We posted signs that the property had been sold, it is private property, there is no trespassing, and all trails leading into and out of the property would be closed on X date, about 2 months later. We posted signs, and wrapped orange caution tape around the areas where the trails crossed my property line. Then we took pictures with dates.
Over the course of the two months, the signs and caution tape were ripped down weekly. I replaced them weekly and took more pictures. On X date, I dropped trees across the trail entrances and wrapped more caution tape around them and took more pictures. The trees got dragged off the trails several times. I put them back several times and took more pictures. Then they dragged the trees about a quarter mile down an abandoned rail line. I dragged them back. I also called the police each time they removed the barriers. Finally, one muddy day, we were able to follow the dirt bike tire tracks down the road to a house a mile away. I called the police again, told them I'd press charges if asked to, and they talked to the parents of the kids. We never had a problem again.
The point is, you can do some things on your own property that you can't do on someone else's property. But in either case, you cannot do things that would cause a person unexpected injury. It's why you can't booby trap your house or property with injurious devices.
And while you may think that you won't lose a lawsuit brought by a trespasser against you, who is also a trespasser with no legal permission to be on that property, and was not charged with enforcing the property owners no trespassing sign, well, let's just wait and see how that turns out when you're forking over a couple hundred thousand dollars because some kid on a bike breaks his collar bone on a piece of concrete you set in a trail with the specific intent to impede people from using that trail. You're intent was to prevent something you had no right to prevent. And you caused injury to the kid, who'd been through that trail a hundred times before and had no reasonable expectation that he'd run into a chunk of concrete put there by you.
I guarantee you'll lose in court.
