Abstract: The blade assembly comprises a circular rotor body with an axial bore for attachment to a motor shaft of a lawn mower and a plurality of spaced cutting elements are attachable adjacent the rim of the body. The rotor body has a plurality of radially elongated passageways near the rim wherein cutting elements, formed as hook members, are positioned. The cutting elements have a radially extending leg for cutting grass and are generally pivotable when so mounted. The passageways are formed with respect to the dimensions of the cutting element to allow limited movement in the vertical direction. Another plurality of passageways are circular in shape and are formed very close to the rotary body rim to allow for greater vertical movement of the cutting elements installed therein to enhance its passage over uncuttable obstacles encountered in operation and thereby reduce the damage done to the cutting element.