A system (42) and computer-implemented method for sensing an amount of ash in cut crop material and automatically adjusting an operating parameter of a mower conditioner to optimize the amount of ash. A sensor (50) measures an measured ash content value of the crop material after it is cut, a processor (48) compares the actual value to a threshold value, and if the actual value exceeds the threshold value, automatically adjusts an operating parameter, such as a height, angle, or speed at which the crop material is cut, a float pressure of the header (12), or a ground speed of the machine (10). Other sensors (64) may measure a roughness of the cut, an excessive stubble height, or other data relevant to optimizing quality, which may also result in adjustments to the operating parameters. The processor (48) may consider an operator-selectable value weighting the measured ash content versus a speed of operation when adjusting the operating parameter.
