Believe it or not, the biggest cause of erosion on green lanes is...............................................................................................................water! I have been riding on lanes that have literally turned into streams/rivers during periods of heavy rain. Why cant everyone get along in the countryside? Its not exactly nose to tail with bikes and 4x4's on lanes is it? I agree that people who break the law and drive/ride on illegal lanes should be prosecuted but I have had arguements with walkers on legal lanes in the past, and have even been threatend with acts of violence! That was pretty funny to be honest as I was suited and booted in body armour and a helmet!
I would suggest joining the trail riders fellowship.