Abstract: A tree shearing apparatus including a main frame mountable on support arms of a machine, a pair of pivot pins mounted on the main frame, a blade support arm mounted on each of the pivot pins for pivotal movement about the axis of that pivot pin, a cutting blade having a leading cutting edge mounted on each of the blade support arms, an element mounted on the main frame that pivots the blade support arm thereby moving the leading cutting edges toward and away from each other, causing the leading cutting edges to sever a tree trunk or the like positioned between them, and an element mounted on the main frame and operatively connected to at least one of the pivot pins that adjusts the attitude of the pivot pin and correspondingly adjusts the inter-relationship of the positions of the leading cutting edges of the blades.