Timber,
In many areas there are checker board patches of timber land with the roads going through both state and private land. While it is true that the roads are used by the public, the timber companies get a lot of value through their use and use the public owned section of the roads to get to much of their land. Often they will close up these roads, cutting off access to public land, but at the same time will use these to access their land and land they own beyond the public land. It seems to me that if they feel the need to cut off road access through their land to the public, the state should cut off access through the state land to them.