Abstract: A depth indicator and automatic control device to indicate and control the position of an earth cutting blade, being drawn by a tractor, with respect to the surface of the terrain over which the tractor wheels of the prime mover pass, as it draws the blade through the ground. Provision is made to readily compensate the position of the cutting edge of the blade with respect to the normal surface of the ground over which the tractor wheels move, so as to enable the depth of the cut to be accurately determined and also enable the adjusting of the device remotely from the earth moving blade, and while the earth moving device is in operation. Provision is also made to enable the blade to be maintained a controlled distance above the ground for spreading material that is being discharged.