In an aerator including a chassis mounted on wheels, a tine depth stop mechanism includes a base mounted on the chassis. A side wall is fixed to the base and has a plurality of apertures therein. A stop arm is movably mounted with respect to the side wall and has an abutment. The abutment has a periphery. A tine weldment is attached to the stop arm, and a tine wheel is rotatably mounted to the tine weldment. A pin passes through one of the apertures of the side wall and engages the periphery of the abutment of the stop arm. Upon a downward movement of the tine wheel, the stop arm moves with respect to the side wall until the pin abuts the periphery of the abutment, thus adjusting a maximum depth of the tine wheel below the chassis.
