An agricultural machine for harvesting forage including a frame supporting at least one device for picking up plants lying on the ground and at least one device for moving the plants that have been picked up. The machine includes a device for guiding the plants which is situated at least partially above and at a short distance from the pickup device and which is supported by arms which extend rearward above the moving device and whose rear ends are articulated relative to the frame by means of substantially horizontal axes situated, during work, above the rear portion of the moving device and about which they can pivot through a certain angle.