http://www.oregon.gov/OPRD/ATV/Permits.shtml
Permits From Other States
An ATV/OHV operating permit that is issued in another state shall be honored in the State of Oregon if the issusing state also honors an Oregon ATV operating permit. The ATV must have a resident state ATV/OHV operating permit or a State of Oregon ATV operating permit to operate the ATV on designated ATV areas. A State of Oregon ATV operating permit may be issued for all terrain vehicles owned by a resident of another state that does not have a permitting program.
Oregon will honor off road permits from the following states:
Alaska
California
Colorado
Idaho
Illinois
Indiana
Missouri
Montana
North Dakota
Pennsylvania
South Carolina
Utah
Vermont
Washington
Wisconsin