An agricultural harvester includes a chassis; at least one ground engaging traction member held by the chassis; a cutter held by the chassis; a sensor held by the agricultural harvester so that the sensor is directed in front of the cutter and configured to emit and receive sound and/or radio waves and produce a plurality of output signals; and an electrical processing circuit coupled to the sensor. The electrical processing circuit is configured to produce a field map from the plurality of output signals and adjust an operating parameter of the agricultural harvester based on the field map.