A hay bale bundler machine to receive individual bales of hay or other forage material from a field and to create a bundle of individual bales wrapped with a wrapping material for discharge back to the ground. Further included may be a fully automatic device that can be mounted directly to a hay baler to receive bales without them being discharged to the ground and to assemble such bales on the hay bale bundling machine for wrapping. The wrapping of the stack of bales to form a bundle proceeds by grasping the stack with a rotatable clamping means and removing the support surface from beneath the stack in order to permit rotation and wrapping of the stack to occur.