Missouri has, for a long time, clearly marked the beginning and end of state maintenance with small signs such as these. But they've always said "State Maintenance Begins" (or ends). In Crowder State Park in Grundy County, at the eastern end of Missouri 128, this sign said "MoDOT" rather than "State". Perhaps this was because the rest of the road is maintained by the state parks department.
This photo was taken in September 2012. The sign is paired with a companion sign on the other side of the road.