Doesn't say anything about a “licensed” vehicle or anything needing a drivers’ license. If you are operating an unlicensed vehicle (let the tags expire perhaps), still counts, as does driving a go-cart, doesn't matter, you are on a public street and driving while drunk.
I suppose every other state is nearly the same. You operate a motor vehicle while drunk, you are “toasted.”
A lawn mower is a yard tool, not a “motor vehicle”. If it’s not covered by statute, the court will have to settle for less than DUI. That’s my story and I’m sticking to it.