Apparatus in which a spring affects movement of a group of said earth working elements so as to change the angle of the axis or axes of rotation of the elements in plan view.
(a spring; affects; movement of a group of said earth working elements; so as to change the angle of the axis or axes of rotation of the elements in plan view)
a spring
affects
movement of a group of said earth working elements so as to change the angle of the axis or axes of rotation of the elements in plan view