Felling a large tree is extremely hazardous, involving immense forces and unpredictable variables. The weight and height of a mature tree mean that a small miscalculation can result in property damage or severe injury. Controlling a multi-ton object falling from a great height requires specialized equipment and training. Improper techniques, such as cutting through the entire trunk, can cause the tree to split upward (a “barber chair”), launching the butt end violently backward over the stump. Given these risks, this job is consistently best performed by certified arborists who possess the necessary knowledge and machinery.
Essential Safety Preparation and Equipment
Before any cutting begins, wearing Personal Protective Equipment (PPE) is mandatory for anyone operating a chainsaw. Head protection is required, typically a hard hat equipped with a wire mesh face shield to guard against flying debris and ear defenders to mitigate hearing damage. The most important piece of clothing is a pair of chainsaw chaps or pants, which contain aramid fiber designed to instantly stop the cutting chain upon contact. Sturdy, steel-toed boots with slip-resistant soles are necessary for firm footing and protection from dropped logs or tools.
Selecting the right chainsaw depends on the tree’s diameter. The guide bar should be at least two inches longer than half the tree’s diameter for a single cut. For a large tree requiring cuts from both sides, the bar length should be at least one-third of the trunk’s diameter. Essential non-cutting tools include felling wedges, which are driven into the back cut to prevent the saw bar from pinching and to help push the tree over.
Ropes, a breaking bar, or a cant hook should also be on hand to assist with directional control or to manage the trunk once it is on the ground. The entire work area must be thoroughly cleared of brush, debris, and any ground hazards that could impede a rapid retreat.
Analyzing the Tree and Planning the Fall Direction
The planning phase requires a careful assessment of the tree’s physical characteristics and the surrounding environment. The tree’s natural lean is the default direction it will favor, determined by inspecting the crown’s weight distribution and the trunk’s curvature. Wind speed and direction must be factored in, as even a light breeze can alter the fall path of a partially cut tree. The trunk should also be inspected for rot, decay, or large dead branches, often called “widow makers,” which could fall prematurely.
The desired fall path must be clearly defined, accounting for the tree’s full height plus a safety margin to avoid structures or property lines. Once the fall direction is established, two distinct escape routes must be identified and cleared of all obstacles. These routes should extend outward from the stump at approximately a 45-degree angle away from the planned direction of fall. This diagonal path allows the operator to retreat safely, moving away from the dangerous zone of the stump where the tree butt can kick back or swing sideways.
Executing the Felling Cuts
The standard method for controlling the fall of a large tree involves a three-cut sequence that creates a directional notch and a hinge. The process begins with the face cut, which removes a wedge on the side facing the intended direction of fall. The first cut of the notch is made horizontally and should penetrate the trunk to a depth of one-fifth to one-third of the tree’s diameter. This depth ensures the hinge will be structurally sound enough to guide the tree.
The second cut is the sloping cut, made at an angle (usually 45 to 70 degrees) until it meets the horizontal cut, allowing the wedge to be removed cleanly. The resulting open-faced notch serves as the mouth into which the tree will fall, ensuring the crown’s weight is directed correctly. This notch creates the initial stress point, concentrating the forces of the fall in the desired direction.
The final cut is the back cut, made horizontally on the opposite side of the tree from the notch. This cut must be positioned slightly higher than the horizontal cut of the notch, typically one to two inches above its apex. Leaving this height difference creates a “step” that helps prevent the tree from kicking back over the stump (butt-rebound). The back cut proceeds until the hinge—an uncut section of wood—remains between the back cut and the notch.
The hinge acts as the structural guide that controls the tree’s momentum and direction of fall. It should be of uniform thickness across the trunk, ideally about ten percent of the tree’s diameter. Its length should be roughly 80 percent of the diameter at breast height. Cutting too far into the hinge removes this control, causing the tree to twist or fall unpredictably, while leaving it too thick can prevent the tree from falling completely.
Dealing with the Drop and Troubleshooting Hang-Ups
As the back cut approaches the hinge, the sawyer must listen for the sound of wood fibers beginning to tear, signaling the start of the fall. If the tree does not immediately start to fall, felling wedges should be quickly inserted into the back cut and driven in to push the tree over. Immediately after the tree begins to move, the operator must shut off the saw and swiftly retreat along one of the two pre-cleared escape routes, keeping an eye on the crown. Move far enough away to avoid the area around the stump and the path of the falling trunk.
A dangerous scenario occurs when the falling tree gets caught in the branches of a standing tree, resulting in a “hang-up.” A hung-up tree is under immense, unpredictable tension and poses an extreme risk of sudden, uncontrolled movement. Attempting to cut down the tree it is lodged against or felling another tree onto the hang-up is strictly forbidden, as this can cause the lodged tree to slide, swing, or drop violently. The safest method for dealing with this situation is to use a winch, a tractor with a long cable, or a turning hook to pull the tree down from a safe distance. If mechanical equipment is unavailable, stop work, mark the area with high-visibility tape, and immediately contact a professional arborist.