A base frame supports pairs of parallel compressing arms having a pivoted depending support on an upper extension. These arms are operated between open and bale forming positions by fluid operated cylinders. An article holding cartridge has upstanding ribs arranged to confine articles therebetween for baling. The ribs are spaced such that upon moving the loaded cartridge into place on a cross conveyor, the compressing arms thread through the ribs and compress the articles. The upper extension has powered lifting and lowering means for operation of the compressing arms in a baling sequence and also to open the arms rearwardly for ejecting the bale. Upper straps are associated with the compressing arms to compress the top portion of the bale, and banding mechanism is supported on the frame for applying bands around the bale. The base frame is supported on a wheeled chassis and has longitudinal adjustment on the chassis for positioning between a rear baling position and a forward road traveling position.