From the Korean War collections:

This photograph is from the Jim Mullings Korean War Collection. Mullings (KWP-1) served in the Korean War for eleven months beginning in January of 1951 with Battery “B” of the 937th Field Artillery Battalion, a federalized Arkansas National Guard unit.

Soldiers from the 937th Field Artillery Battalion posed in front of "Bulldog's Bark," a 155mm Long Tom, unidentified location, Korea, 1951.