Abstract: A baler adapted for towing by a tractor to pick up a windrow of hay and roll the hay into a cylindrical bale of substantial size and weight. The baler includes a front mounted pickup and a bale forming structure directly behind the pickup. The bale forming structure is of the type including an endless lower belt and a plurality of upper belts defining an expansible bale forming zone in conjunction with the lower belt. Suitable bale-density and bale-discharge structures are included. The baler includes a wheeled frame which provides a pivot connection for a draft tongue laterally offset from the baler centerline. The draft tongue extends forwardly for hitching to a tractor which can be disposed in towing relation alongside the windrow. A hydraulic cylinder is mounted between the baler frame and the draft tongue for powered steering of the baler relative to the windrow.