A lot of the timber companies just use those for designation instead of calling them by a name. Capitol State Forest has an A,B,C, and D line. On national forest lands you'll see a FS2270 or something like it. The FS stands for forest service road. Some companies just use numbers for their roads. Check out google earth as it can do a lot of your scouting for you and save you a lot of walking. You can also buy a Public Lands Quadrangle map that has most of the lands labeled so you know the different ownerships.