A swather includes a swath compression panel with a downwardly and rearwardly inclined undersurface for applying a downward compression force on the swath between the front and rear wheels. A mounting assembly includes an actuator operable in response to a speed and/or direction of travel of the tractor for raising the panel to a retracted position under the tractor. A bottom stop halts downward movement of the actuator before the panel engages the ground. The panel includes an upwardly and rearwardly inclined curved rear portion to smoothly release the compressed crop. The panel is mounted on the tractor frame at a position thereon rearward of a transverse beam connected to the front wheels so that the swath is released from the discharge opening of the header and can expand for discharge to the ground before the swath is engaged by the front end of the panel.