I am attempting to locate Camp Russel, AR

One of my ancestors, John DYSON [Franklin Co.], served in the Missouri State Guard and then in Co. E 5th MO Inf. He was discharged near Tupelo MS 18 June 1862. He was unable to return home, traveled around Texas, was in Carroll Co. AR in Aug. of 1862, heading to Little Rock [Lee Co.] AR and near Yellville [Marion Co.] AR later that year. He seems to have re entered the service before Feb. 1863 [at least he was paid at that time] but his enlistment papers state:

Enlisted: Co. I 4th MO Cav. [Capt. Roberts] 19 June 1863 in Camp Russel, AR

Any idea where Camp Russel was located?

My thanks for your time.