A work machine to cut timber including a control system, a felling head (118), a hydraulic motor (201) configured to adjust the position of the felling head, and a spool valve (216) operatively connected to the hydraulic motor, the spool valve being configured to move the felling head responsively through operation of the hydraulic motor. A machine controller (202) coupled to the operator controller and the spool valve executes stored program instructions to generate a first control signal responsive to an operator control signal provided by the operator controller, generate a second control signal as a function of the generated first control signal, adjust a position of the spool of the spool valve in response to a concurrent receipt of the first control signal and the second control signal by the first proportional control valve (228) and the second proportional control (230) valve to move the felling head through operation of the hydraulic motor.
