In Oregon, drivers under eighteen years of age may not tow trailers. The "Provisional Driver License" issued to drivers aged sixteen through eighteen says it is valid for "[a]ny signle vehicle with a GVWR of not more than 26,000 pounds with the proper endorsements. Any emergency vehicle operated by a firefighter." This license remains valid after the driver turns eighteen; there is no need to replace it to continue driving single vehicles. If the driver wants to start towing trailers (and is not a firefighter), is it necessary to get a new license without the "single vehicle" restriction, or is it implied that this restriction only applies through age eighteen?
I couldn't find the same wording on the Oregon DMV / law websites, but in a Background Brief on the Oregon Legislature website, there is this statement, just after discussion of restrictions on a Class C provisional license:
Upon reaching 18 years of age, individuals may qualify for a standard Class C license. This license allows the bearer to operate vehicles under 26,000 pounds, recreational vehicles, fire and emergency vehicles, and to tow other vehicles and trailers with certain weight restrictions.
Emphasis mine. The document is from 2012.