Felling a large tree requires meticulous planning and precision due to the immense, uncontrolled energy released during the fall. A “big tree” is typically defined as one taller than the cutter is experienced with, or one that requires specialized control equipment like felling wedges. Success hinges entirely on preparatory work and the accurate placement of specific cuts, which steer the tree’s fall path. Precision is necessary to prevent serious injury, catastrophic property damage, or death.
Essential Safety Gear and Site Preparation
Before any cutting begins, the proper selection and use of personal protective equipment (PPE) is mandatory. Head protection, such as a forestry helmet, shields the user from falling debris or branches. Eye and ear protection are also required, with safety glasses preventing injury from wood chips and earmuffs guarding against the damaging noise of a powerful chainsaw.
The lower body must be protected by chainsaw chaps, which contain ballistic fibers designed to instantly jam the saw chain upon contact. Sturdy steel-toed boots provide ankle support and defend the feet from dropped tools or rolling logs. Essential tools include a high-powered chainsaw appropriate for the trunk diameter, and felling wedges. These non-metallic plastic or aluminum tools prevent the saw from pinching and help push the tree over.
Site preparation centers on establishing a safe and clear escape route, which must be planned and cleared of all debris before the first cut is made. This path should be positioned at approximately a 45-degree angle away from the direction of the intended fall and the stump. Selecting two distinct escape paths, one on each side, ensures the feller has immediate options, as moving directly backward is hazardous due to the potential for the trunk’s butt to kick back. The entire area of the fall zone and the escape paths must be kept clear of obstacles to allow for a rapid retreat once the tree begins to move.
Determining the Fall Direction and Tree Hazards
The planning phase starts with a detailed assessment of the tree’s natural lean, which is the most powerful determinant of the final fall direction. Factors like uneven branch distribution, asymmetrical crown weight, and prevailing wind must be considered to accurately predict the tree’s tendency. Felling should be avoided entirely if wind speeds are unpredictable or excessive, as they can override a carefully planned cut.
The trunk must be thoroughly inspected for defects that could cause the tree to split prematurely or fall unpredictably. Signs of decay, rot, or large cavities near the base indicate a compromised structure. This significantly increases the risk of a barber-chair break, where the trunk splits vertically and violently upward. Overhead hazards, such as dead or loose branches lodged in the canopy, must be identified and addressed before felling begins. If the tree exhibits a severe lean or is situated close to structures or power lines, professional arborist assistance is the only safe course of action.
Executing the Directional Felling Cuts
Controlled felling relies on creating a hinge of wood at the base of the tree to guide the weight during its descent. The first step is executing the directional notch, also called the face cut, on the side of the trunk facing the intended fall direction. The notch is formed by two cuts: a downward-sloping top cut, often at a 45-degree angle, meeting a horizontal bottom cut. This wedge-shaped section should remove approximately one-fifth to one-quarter of the tree’s diameter, and its precise alignment determines the fall path.
The remaining section of uncut wood, known as the hinge, controls the direction and speed of the fall. This hinge must be uniform in thickness, usually maintained at about 10% of the tree’s diameter, to provide maximum control while the tree rotates downward. A hinge that is too thick will resist the fall, while one that is too thin will break prematurely, leading to an uncontrolled drop.
The final step is the back cut, made on the side of the trunk opposite the notch, always slightly above the horizontal cut of the notch. This upward offset ensures the back cut does not accidentally sever the hinge prematurely. As the back cut nears the hinge, felling wedges are inserted into the cut to prevent the saw bar from pinching and to begin exerting force. Once the back cut is complete and the tree begins to move, the feller must immediately shut off the chainsaw, place it on the ground, and quickly retreat along the cleared 45-degree escape path.
Processing the Fallen Tree
After the tree has safely come to rest, hazards continue, as debris lodged in the canopy may still fall, and the fallen trunk is under various tensions. Once the area is confirmed safe, the process of limbing, which is the removal of branches, can begin. Limbing should start from the base of the tree and proceed toward the top, with the operator always standing on the uphill side of the log where possible.
Bucking is the subsequent operation of cutting the long trunk into manageable sections. This stage requires careful attention to the forces of tension and compression within the log, caused by the log resting on uneven ground. Cutting the compression side first can cause the saw to pinch and bind, while cutting the tension side first may cause the log to split or roll. To avoid these reactions, a common technique involves making a shallow under-cut on the compression side first, followed by the final cut from the tension side.