By providing an electronic control system in communication with a hydraulic system for adjusting an angle of smoothing tools of a harrow, the smoothing tools may be adjusted more quickly and on the go, including from a tractor cab, for optimum field leveling during a tilling session. The control system may include a hydraulic control valve in communication with a linear actuator. The linear actuator may be in communication with a slide bar disposed in a channel. By configuring multiple bars of a harrow to achieve an angle of rotation defined by the slide bar, the angle of rotation for smoothing tools of the harrow may be precisely controlled by the control system.

By providing a hydraulic system for configuring an angle of rotation for smoothing tools of a harrow that is predetermined for a tilling session, hydraulic pressure of the hydraulic system may be maintained (and not adjusted) to allow the hydraulic system to actuate during the tilling session by tilling forces encountered by the smoothing tools. As a result, the angle of the smoothing took may change during the tilling session, thereby allowing excessive plant residue encountered by the smoothing tools to be passed over to minimize plugging or bunching.

By providing a hydraulic system for configuring an angle of rotation for smoothing tools of a harrow that is predetermined for a tilling session, hydraulic pressure of the hydraulic system may be maintained (and not adjusted) to allow the hydraulic system to actuate during the tilling session by tilling forces encountered by the smoothing tools. As a result, the angle of the smoothing took may change during the tilling session, thereby allowing excessive plant residue encountered by the smoothing tools to be passed over to minimize plugging or bunching.

By providing a linear actuator in communication with a slide bar disposed in a channel, and by configuring multiple bars of a harrow to achieve an angle of rotation defined by the slide bar, the angle of rotation for smoothing tools of the harrow may be precisely controlled by the linear actuator. As a result, an infinite range of downward angles may be available for the smoothing tools for achieving various effects with the soil.

By providing a linear actuator in communication with a slide bar disposed in a channel, and by configuring multiple bars of a harrow to achieve an angle of rotation defined by the slide bar, the angle of rotation for smoothing tools of the harrow may be precisely controlled by the linear actuator. As a result, an infinite range of downward angles may be available for the smoothing tools for achieving various effects with the soil.

A harrow attachment for a tillage implement includes a harrow drawbar mounting at least one rank of harrowing tools. A pivot link pivotally couples the harrow rank to the drawbar so it can trip by pivoting upward toward the drawbar from a home position in which the harrow rank is farthest away from the drawbar. A downforce spring is coupled to the drawbar and in a variable length state when the harrow rank is tripped to apply a return biasing force to the harrow rank. An adjustment mechanism couples the spring to the harrow rank and/or the pivot link in one of a plurality of adjustment locations in each of which the harrow rank is in the home position and the spring is in a fixed length state in which the biasing force is removed.

A harrow attachment for a tillage implement includes a harrow drawbar mounting at least one rank of harrowing tools. A pivot link pivotally couples the harrow rank to the drawbar so it can trip by pivoting upward toward the drawbar from a home position in which the harrow rank is farthest away from the drawbar. A downforce spring is coupled to the drawbar and in a variable length state when the harrow rank is tripped to apply a return biasing force to the harrow rank. An adjustment mechanism couples the spring to the harrow rank and/or the pivot link in one of a plurality of adjustment locations in each of which the harrow rank is in the home position and the spring is in a fixed length state in which the biasing force is removed.

A spike tooth harrow of a tillage implement includes a plurality of arms configured to couple to a frame section of the tillage implement. The spike tooth harrow also includes a plurality of bars coupled to the plurality of arms, wherein each bar of the plurality of bars includes a plurality of spikes angled relative to a direction of travel of the tillage implement, the plurality of bars are coupled to the plurality of arms via cables, and the spike tooth harrow is configured to extend and to retract the plurality of bars relative to the plurality of arms.

A spike tooth harrow of a tillage implement includes a plurality of arms configured to couple to a frame section of the tillage implement. The spike tooth harrow also includes a plurality of bars coupled to the plurality of arms, wherein each bar of the plurality of bars includes a plurality of spikes angled relative to a direction of travel of the tillage implement, the plurality of bars are coupled to the plurality of arms via cables, and the spike tooth harrow is configured to extend and to retract the plurality of bars relative to the plurality of arms.

A harrow implement comprises a tool bar and harrow sections extending rearward therefrom. Each of a plurality of hydraulic cylinders is connected between the tool bar and a corresponding harrow section. A hydraulic control is operative to supply pressurized hydraulic fluid such that the hydraulic cylinders exert a substantially constant selected bias force on the harrow sections. The hydraulic control is operative to direct pressurized hydraulic fluid into a first port on each hydraulic cylinder to exert a downward bias force on the plurality of harrow sections, and operative to direct pressurized hydraulic fluid into a second port on each hydraulic cylinder to exert an upward bias force on the plurality of harrow sections. The hydraulic cylinder can be configured to raise the harrow sections to an idle position above the ground, and to a transport position extending up from the tool bar.