The man was arrested for drunken driving. The Sheriff's Office says his blood-alcohol level was .190 -- well above Iowa's limit of .08.
Boone County Sheriff Ron Fehr says it's illegal in Iowa to drive any kind of motor vehicle anywhere while drunk.
Fehr wasn't sure how fast the man was going on the six-speed Bolens lawn tractor. The Des Moines Register reports that the top speed for that mower is about 5 mph.