The Ozark Trail goes through federal, state, private, and conservancy lands. The main "authority" is the Ozark Trail Association, a private group.
Still, the National Park Service figures that it might as well claim credit where it can.
The Current River Section of the OT uses a fair amount of land from the Ozark National Scenic Riverways, and national park unit. (Betcha didn't know that!)
March 2010.