At the Missouri State ARchives, Volume 20 of Enrollment Lists, Missouri Militia (this was the second Missouri Militia organized by the state convention), lists Joseph H. Johnson in Co. D, 24th Regiment, which included Iron, Madison, and Wayne counties. Could this be your man? Additional information listed his age as 28, height 5 feet 5 inches, dark hair, blue eyes, light complexion, married and a farmer.