An earth cutting apparatus comprising a plurality of articulated elements including at least a first element having a mounting structure thereon and an adjacent second element hingedly connected to the first element. An earth cutting member is provided including a proximal end which is pivotally mounted to the mounting structure of the first element and an earth cutting end. The earth cutting member is slidably connected to the adjacent second element and moveable between an extended position and a retracted position, such that hinged movement of the adjacent second element relative to the first element causes the earth cutting member to slidably extend from the adjacent second element to the extended position for operatively cutting earth. Hinged movement of the adjacent second element in an opposite direction causes the earth cutting member to slidably retract to the retracted position.