The present invention relates to an improvement to the device for simultaneously cutting and treating a plant stem including at least one cutting blade 104 delimited by two faces 107, 108 defining a cutting line 115, a folding-down blade 100, means for mounting the folding-down blade so that it can pivot with respect to the cutting blade about a first axis of rotation 103 which is perpendicular to the cutting plane, a reserve of treatment product connected by a duct to the cutting blade and opening out through an orifice 109 onto one face 108 of the cutting blade. The improvement according to the invention is characterised in that the means for mounting the folding-down blade 100 so that it can pivot with respect to the cutting blade 104 consist of a backing blade 101, first means 102 for mounting the backing blade so that it can rotate about the first axis 103 with respect to the cutting blade, so that one of its faces 105 is substantially in the plane of the face 107 of the cutting blade which does not include an orifice and of second means 110 for mounting the folding-down blade 100 so that it can rotate with respect to the backing blade 101 about a second axis 111 which is substantially parallel to the cutting plane. <IMAGE>
