Frank, I'm sure that the reference to "Marietta" is a clerical error, and should read "Marianna."
John H. Moore enlisted in Corley's Spy Company in Phillips County on March 11, 1862. Corley's company became Co. A, 1st (Dobbin's) Arkansas Cavalry, and Moore was promoted to fourth sergeant.
Dobbin's regiment rarely operated outside of northeast Arkansas, and spent a lot of time skirmishing in Phillips County.