I don't "own" any trails but I do try to help out on my local trails. I will put some of the trail constructions back together when they get a little discombobulated. Like if there's a rock bridge and the rocks are coming apart I'll re-construct it. The other thing I do is close down the un-official "short cuts" that people create when they ride around obstacles instead of over them. When I see one forming I cover it with sticks and rocks so that people stop short cutting off-trail. yeah, I guess I'm kind of a jerk as far as that's concerned.