The pre-pruner has two cutting assemblies (10, 20), in which each assembly comprises a cutting disk (3) and a feeler-rake disk (4). The disks are parallel and retractable with respect to vine pickets. The cutting assemblies are fixed with respect to each other on a width equal to that of notches of the cutting disks for creating blade and counter-blade effect. The notches of the cutting disks are joined and tapered on their length.