A weed whacker attaches to the front of a riding lawn mower. The week whacker is attached to the riding lawn mower through a pivoting linkage, and is supported on castors which may be adjustable in height. The weed whacker may thereby traverse uneven terrain which differs from the terrain traversed by the riding lawn mower, continuing to provide an even cut over the terrain. The weed whacker draws its power from the riding lawn mower. The weed whacker may be shifted between the right and left sides of the riding lawn mower. The weed whacker may be controlled by the driver of the riding lawn mower, including unwinding additional cutting wire in response to a control signal from a controller used by the driver of the riding lawn mower.