The selective positioning of row units along a planter tool bar is facilitated by introducing an elongated channel of generally C-shaped cross-sectional configuration intermediate the tool bar and a plurality of row unit head brackets. The channel is welded or otherwise fixed to the tool bar with the open edge of the C facing away from the tool bar and the head brackets are fixed to the channel by clamping nut and bolt assemblies. The bolts extend through the clamping brackets and engage corresponding clamping nuts. The clamping nuts are positioned within the C and may be slid along the inner edge of the channel to any preferred position. The bolts are then and tightened fixing the head bracket at the selected at location.

Described is a structural element for agricultural equipment comprising at least one pair of transverse beams associated with at least one pair of support bars of a set of agricultural discs, where the longitudinal distance between the beams of the pair of transverse beams is smaller than the longitudinal distance between the bars of the pair of support bars. This construction allows a greater free space for the flow of material cut by the discs (soil and plant residues) and a decrease in the occurrence of stops to clear the obstruction or even the formation of heaps on the ground, while still promoting an adequate arrangement for the absorption and dissipation of efforts that act on the structural element.

Described is a structural element for agricultural equipment comprising at least one pair of transverse beams associated with at least one pair of support bars of a set of agricultural discs, where the longitudinal distance between the beams of the pair of transverse beams is smaller than the longitudinal distance between the bars of the pair of support bars. This construction allows a greater free space for the flow of material cut by the discs (soil and plant residues) and a decrease in the occurrence of stops to clear the obstruction or even the formation of heaps on the ground, while still promoting an adequate arrangement for the absorption and dissipation of efforts that act on the structural element.