Airmen and volunteers unload Christmas trees during Trees for Troops outside the 28th Force Support Squadron Outdoor Recreation Center at Ellsworth Air Force Base, S.D., Dec. 5, 2014. Tree farms from Iowa, Kansas and Missouri donated 175 trees for the event, providing Airmen with a free Christmas tree to thank them for their service. (U.S. Air Force photo by Senior Airman Zachary Hada/Released)