IDman, it is very sad what is happening to the forest road network. We were recently hiking in the Hoover Wilderness north of Yosemite and saw a lot of new and illegal ATV tracks through meadows and over streambeds. At very high altitudes, it will take many years for those scars to heal, because the growing season is so short.
A few lawbreakers are going to ruin it for everyone else -- the forest service is cutting back on vehicle access in a lot of areas. I don't know what else they can do -- they can't put a ranger on every road. The folks who run their quads cross-country are not the sort of people who read these forums, so there is no way to ask them to stop. They know exactly what they are doing, and they do not care.