An agricultural trailing device in the form of a tractor attachment, such as a mulching device, that is attachable to a tractor, which device comprises a frame, in which an operating member of the trailing device, which is a rotor (2, 2'), is arranged, wherein the rotor (2, 2'), which is accommodated in a housing, extends perpendicularly to the direction of tractor's driving and is connected with the tractor via a power transmission drive assembly, and is pivotally mounted on the frame by means of a lifting support (5, 5'), a mechanism, arranged within the frame, for lifting the rotor from the operating position to the transport position, the lifting support being part of said mechanism, a drive shaft arranged on the trailing device substantially perpendicularly to the direction of tractor's driving, and a Cardan shaft (4, 4') which is connected to the drive shaft with one of its Cardan joints comprising forks and connected with a second Cardan joint comprising forks to the operating member of the trailing device which is a rotor, characterized by having an integrated assembly for the alignment of the Cardan shaft (4, 4') comprising a movement transfer mechanism, a thrust element, and an alignment element, wherein the alignment element is substantially an equilateral prism with four perpendicular sides and is arranged on a transverse drive shaft, such that two mutually parallel sides of the alignment element are parallel to the inner forks of the second Cardan joint and the other two mutually parallel sides of the alignment element are parallel to the outer forks of the second Cardan joint, wherein the thrust element is formed as an elongate element and is arranged on the trailing device frame, so that its longitudinal axis is perpendicular to the transverse drive shaft and that its lower surface facing the ground slides in translation along one of the sides of the alignment element when the latter is in the N*90° position, wherein the movement transfer mechanism is formed to convert the rotary movement of the lifting support into a translational movement of the thrust element in a non-linearly synchronized manner. mulching device, that is attachable to a tractor, which device comprises a frame, in which an operating member of the trailing device, which is a rotor (2, 2'), is arranged, wherein the rotor (2, 2'), which is accommodated in a housing, extends perpendicularly to the direction of tractor's driving and is connected with the tractor via a power transmission drive assembly, and is pivotally mounted on the frame by means of a lifting support (5, 5'), a mechanism, arranged within the frame, for lifting the rotor from the operating position to the transport position, the lifting support being part of said mechanism, a drive shaft arranged on the trailing device substantially perpendicularly to the direction of tractor's driving, and a Cardan shaft (4, 4') which is connected to the drive shaft with one of its Cardan joints comprising forks and connected with a second Cardan joint comprising forks to the operating member of the trailing device which is a rotor, having an integrated assembly for the alignment of the Cardan shaft (4, 4') comprising a movement transfer mechanism, a thrust element, and an alignment element, wherein the alignment element is substantially an equilateral prism with four perpendicular sides and is arranged on a transverse drive shaft, such that two mutually parallel sides of the alignment element are parallel to the inner forks of the second Cardan joint and the other two mutually parallel sides of the alignment element are parallel to the outer forks of the second Cardan joint, wherein the thrust element is formed as an elongate element and is arranged on the trailing device frame, so that its longitudinal axis is perpendicular to the transverse drive shaft and that its lower surface facing the ground slides in translation along one of the sides of the alignment element when the latter is in the N*90° position, wherein the movement transfer mechanism is formed to convert the rotary movement of the lifting support into a translational movement of the thrust element in a non-linearly synchronized manner.