Have you guys heard about this, think it's been in effect since last year.
Basically, the National Forest System is publishing maps designating routes that are open to motor vehicle travel.
From what I understand, if the route is not on the map, you're not allowed on it - it may or may not be signposted.
From what I can see there's only a few small roads that I ride that are not on the map, and, I spend most of my time on state BLM roads/routes.
Anyways, something to be aware of........
Here's the link where you can read more and download maps :
Willamette National Forest- Maps