An agricultural row unit includes a hydraulic cylinder coupled to a support member for urging a soil-engaging tool coupled to the support member downwardly toward the soil. A hydraulic line is coupled to the hydraulic cylinder for supplying pressurized hydraulic fluid to the cylinder, and a controllable valve is provided in the hydraulic line for controlling the supply of pressurized hydraulic fluid to the cylinder through the line. A pressure sensor, such as a load cell or strain gauge, is connected between the hydraulic cylinder and the support member for producing an electrical signal corresponding to the pressure on the tool, and a controller is coupled to the pressure sensor and the controllable valve, the controller being adapted to receive the electrical signal from the pressure sensor and produce a control signal for controlling the valve thus the supply of the hydraulic fluid to the cylinder.
