An agricultural machine for working soil or for sowing seeds, including a trailed chassis and work elements distributed on a longitudinal bar in plural sections, the longitudinal bar including at least two primary beams extending substantially transversely to a direction of advance in a work configuration. A secondary beam is connected to each primary beam by two connection devices, the secondary beams support the work elements, and each secondary beam rests on the soil by two support wheels and is configured to move freely during work to follow a profile of the terrain.