A planting system including a plurality of seeding row assemblies, each having components maintained at a controlled elevation. The seeding row assembly includes a tillage row unit controlled to maintain a desired elevation relative to a seeding row unit, the seeding row unit being configured to passively follow the local terrain. Each seeding row assembly can include two position sensors that generate signals corresponding to the elevation of the seeding row unit and the ground engagement attachment, respectively, or a differential position sensor that generates signals corresponding to the difference in the elevations. Various embodiments include a local closed loop controller that adjusts elevation of the tillage row unit relative to the seeding row unit to a desired set point. In some embodiments, the down force of the seeding row unit is actively controlled.
