the front end 19 a or back end 19 b of the frame 19 and substantially parallel to the surface upon which the plow is traversing the tension exerted by position correction device 10 on the blade 16 in returning to the original position can be adjusted in at least one embodiment as shown in the embodiment of fig6 the box 12 has a dial 26 on its proximal portion for purposes of adjusting the tension the dial 26 can be turned in one direction in order to increase the tension of the position correction device 10 located inside the box 12 and turned in another direction to decrease the tension of the position correction device 10 in at least one embodiment as shown in the embodiment of fig7 the position correction device 10 is a spring the spring 10 is movably engaged to the plow blade 16 and to a threaded eye bolt 10 a the bolt 10 a has threads that match the dial 26 as the dial 26 is turned in one direction the threaded portion is advanced further through dial 26 and thus bolt 10 a is moved in a direction away from the blade 16 thereby increasing tension on the spring 10 and concomitantly increasing the resistive force applied to.