in the early American army on high-ranking officer's headwear and may have come from the British or Germans as oak leafs and acorns were used in German uniforms in the 18th Century. The Army and US Air Force oak leaf is a stylized silver leaf that does not represent any individual tree. The Marine Corps version is styled like a navy Commander's and is similar to a southern live oak leaf grown in the Naval Live Oaks Reservation in the 19th Century.

Promotion to lieutenant colonel is