Though not specifically mentioned in either DA 670-1 or AR 670-1, shoulder cords in branch colors may be authorized for wear by a local U.S. Army Commander. Typically this is done for a special ceremonial event, but ultimately the parameters of wear are at the Commander’s discretion.
Orange and white are the official colors of the Signal Corps. Orange was named the Signal Corps sole branch color in 1872, a dozen years after the Corps’ de facto creation by Congressional appointment of Albert J. Meyer as the lone officer in the “Signal Department.” Three decades later, the Army added white piping to the colors so that the Corps’ colors would conform to the prescription that only Line branches (Artillery, Infantry, Cavalry) would be assigned a single branch color.
Orange and white shoulder cords may also be worn by members members of Junior ROTC affiliated with the Air Force or Navy.