Cutting a wedge into a tree, known as a directional notch or face cut, is a fundamental technique in controlled tree felling. This precise removal of wood determines the exact direction the tree will fall, guiding it away from hazards. The technique establishes a guide system in the trunk, ensuring the tree’s descent is predictable and manageable. Executing this wedge correctly is the primary mechanism for maintaining control and maximizing safety.
Essential Safety Gear and Site Assessment
Personnel must complete a thorough assessment of the environment and wear personal protective equipment before cutting. Protective gear includes a hard hat, eye protection, and hearing protection against debris and noise. Chainsaw chaps or protective trousers, designed to stop a moving chain, are necessary for lower body defense.
A careful evaluation of the tree is required to identify its natural lean and the presence of overhead hazards, such as dead branches known as “widowmakers.” The ground surrounding the tree must be cleared of debris and brush to establish unhindered retreat paths. These paths should be planned at an approximate 45-degree angle away from the anticipated line of fall.
Understanding the Geometry of the Felling Notch
The directional felling system comprises the face notch, the hinge, and the back cut. The face notch is the wedge removed from the side of the tree facing the desired direction of fall. For maximum control, the two cuts forming this notch should create an opening angle of 70 to 90 degrees, known as an open-face notch.
The notch depth should extend approximately one-fifth to one-third of the tree’s diameter into the trunk. This ensures sufficient material remains for the hinge. The hinge is the strip of uncut wood left between the apex of the face notch and the back cut, guiding the tree’s descent. This holding wood should be uniform, ranging from 5 to 10 percent of the tree’s diameter, and must remain intact until the tree falls.
Creating the Face Cut
Creating the face cut involves two precisely aligned cuts. The first is the sloping cut, the upper cut made downward at an angle of 70 to 90 degrees to form the top of the wedge. The operator can use the felling sights marked on the chainsaw body to aim this cut accurately toward the intended fall line.
The second is the horizontal cut, made perpendicular to the trunk, which meets the sloping cut exactly at the predetermined apex. These two cuts must meet cleanly without overlapping so the wedge can be removed precisely. This clean removal creates a sharp, defined point at the notch apex, establishing the front edge of the guiding hinge.
Completing the Back Cut and Using Felling Aids
The back cut is made on the opposite side of the tree from the face notch. This horizontal cut extends toward the face notch but stops short to leave the hinge intact. For an open-face notch, the back cut is positioned at the same level as the apex of the face cut, or slightly above it, to prevent the tree from kicking back off the stump.
A felling wedge, constructed from plastic or metal, can be inserted into the cut kerf as the back cut deepens. This prevents the saw bar from becoming pinched by the tree’s weight. The wedge also acts as a lever to help push the tree over, particularly those with a slight back lean. The wedge is tapped firmly into the kerf, alternating with cutting until the hinge is the correct thickness.
Once the tree begins to move and the hinge starts to break, the operator must immediately remove the saw. They must then retreat rapidly along the pre-planned 45-degree escape route, watching the tree for any unexpected movement.