Control of base cutter height for multiple row sugar cane harvesters

A sugar cane harvester comprising:

• a chassis powered for movement across a field in a forward direction;
• a sugar cane row divider;
• a base cutter positioned downstream of the sugar cane row divider for severing stalks of sugar cane in individual rows;
• a linkage connected to the chassis for variably positioning the base cutter relative to a field surface;
• an actuator for variably positioning the base cutter from the field surface;
• a position sensor in the linkage to generate a signal indicating a position of the base cutter relative to the field surface;
• a controller configured to receive a signal from said position sensor for maintaining the base cutter at a preselected height;
• and
• a load sensor between the linkage and the chassis of the harvester for detecting and generating a signal representative of a load, wherein the controller is configured to determine when the signal from the load sensor drops indicating ground contact between the base cutter and the field surface for elevating the base cutter.