Are they required to label the 2-track oil roads as "private"? Are they marked as such?
If they are public land it is ok to use them unless they are marked "private road" you will find about half of the roads will be marked with signs. A second concern about roads on public lands is to be aware of the "off road travel restrictions" of the land you are on(forest service, blm, etc) the 2 tracks may be off limits even if they are not marked private.
Honestly the best approach is to assume you will be restricted to the main roads and walk in. I take my game cart, I can't drive down the roads but nothing says I can't walk down it pulling my game cart in and out. Makes for easy pulling.
