Air Force Col. Christopher Callis, 509th Mission Support Group commander, hands scrap wood to another volunteer on March 30, 2019, on a farm in Knob Noster, Missouri. Callis led a group of 509th Security Forces Squadron Airmen from Whiteman Air Force Base, Missouri, in a volunteer effort to assist a local Vietnam War veteran and former security policeman to clear his property. (U.S. Air Force photo by Staff Sgt. Kayla White)