Our local highway district actually makes this data available for free so I checked, its not in there. I also called them and asked about it and the lawyer seemed annoyed that google was adding county easements as public roads too since they alone should have access. So its not coming from the county at least. Its also marked roads where farm tracks are that are not in any way associated with public roads or access. I suspect that there is something looking at the photos taken by aircraft and thinking "that looks like a road!" or something because nothing else would make sense. Why mark something as a road that is just a space between two crops that is driven by tractors?

Also worth noting, its not on OOSM or Bing.. Only Google. So the source is something that only Google is using.