A bale stacker for forming a number of bales into a bale bundle having a predetermined number of bales. The bale stacker includes a compression chamber in which the bales are formable into the bale bundle, and a loading chamber in which the bales are positionable in respective columns proximal to an upstream opening of the compression chamber. The bale stacker also includes a transfer assembly with a platen for moving the columns from the loading chamber into the compression chamber. Front doors are located at the upstream opening and movable between a closed position, in which the upstream opening is at least partially obstructed by the front doors, and an open position, in which each column of bales is movable respectively through the upstream opening. Controlling means coordinate movement of the front doors with movement of the platen.
