Sounds like something right out of Carry_Okie's book.
Good to see someone finally alive and functioning on this site tonight, just about the time I gotta leave. It's been dead here.
If the tresspasser is injured because of an "unsafe condition" on the land, the land owner is not only liable, but subject to penalities. What might such an unsafe condition be? How about the ATV driver running into a barbed wire fence? One then may have to convince a jury that one was not negligent because he had a fence to keep the cows in. Most city dewllers have no concept of what is required to operate a farm.