The invention relates to an attachment device (2) for harvesting stalky stem material (6), comprising: stem dividers (4) cutting devices (8) for cutting off the stalky stem material (6) conveying devices (10) for conveying the cut stalky stem material (6) away a number of picking units (12) distributed over the working width of the attachment device (2) for separating crops from the stalks, each picking unit having at least one picking roller (14) and a picking gap (16) associated with the picking roller (14) a milling device (18) associated with each picking unit (12) for the stalks and a device (20) for collecting and bringing together removed crops. In order to create an attachment for which the losses of stalky stem material are lower when the attachment device is not guided exactly along the rows of plants, at least one drivable stalk support (22) is associated with each picking unit (12), the stalk support being arranged in front of the associated picking unit (12) in the driving direction (F) and at a height distance from the picking unit (12) and from the cutting devices (8), wherein the stalk supports (22) are arranged on one or more pivotable retaining arms (32), and the stalk supports (22) can be moved in the longitudinal direction and/or in the height (H) thereof and/or in the angle of attack thereof and/or can be adjusted in the rotational speed thereof.
