A tillage apparatus having a rotary harrow mounted thereon with mounting elements utilizes a cooperative combination of: a compressible material at the mounting element to permit relative motion between the harrow and the mounting element in response to a motion of the harrow; and, a hydraulic actuator operated under a first pressure to lower the rotary harrow and maintain engagement of the rotary harrow with the ground. A pressure relief element is utilized to reduce back pressure in response to the harrow striking a hard impediment on the ground during operation of the tillage apparatus in a field. The combination cooperates to reduce damage to the harrow and/or other parts of the tillage apparatus when the harrow strikes a hard impediment such as a rock.