Felling a tree with a chainsaw is a task that combines mechanical power with the physics of a large, falling object, requiring a high degree of respect and technical skill. The process involves a specific sequence of preparation, cutting, and processing that must be followed for personal safety and to control the tree’s final resting place. Understanding the forces at play and the correct steps for each phase of the operation is foundational to successfully bringing a tree down.
Essential Safety and Site Preparation
Before starting the engine, the operator must be fully equipped and the work area thoroughly assessed for hazards. Personal Protective Equipment (PPE) is the first layer of defense against the high-speed chain and falling debris.
This gear includes:
- A hard hat to protect against overhead hazards.
- Approved safety glasses or a mesh face shield for eye and face protection.
- Hearing protection to guard against the saw’s noise levels.
- Cut-resistant chainsaw chaps or trousers, mandatory for protecting the upper thigh.
- Sturdy leather or steel-toed boots with ankle support for firm footing and protection.
Site preparation begins with determining the tree’s height and lean, which dictates the safe felling zone and primary fall direction. A simple method for estimating height is the “stick method,” where a stick equal to the distance from your eye to your outstretched hand is used to sight the tree’s top and base. The intended felling direction must be at least twice the tree’s height away from any structures, power lines, or people.
Once the felling direction is established, two clear escape routes must be prepared, leading diagonally away from the planned fall path at roughly a 45-degree angle. These paths should be cleared of brush and obstacles to ensure an unimpeded retreat once the final cut is made. The area immediately around the trunk also needs to be cleared of debris to allow for stable footing while making the cuts.
Executing the Directional Felling Cut
The directional felling cut is a precise, two-part operation designed to control the tree’s direction and speed as it falls. This process begins with creating the directional notch, also known as the face cut or undercut, on the side of the tree facing the intended fall direction. A common method is the open-face notch, which uses a top cut and a horizontal bottom cut that meet to remove a wedge of wood.
The top cut is angled down, typically between 60 to 80 degrees, and should aim to penetrate about one-fifth to one-third of the tree’s diameter. The horizontal bottom cut meets the angled top cut to form the notch, which acts as the hinge’s release point and directs the fall. A large opening angle is preferred because it keeps the guide wood—the hinge—intact longer, providing greater control during the fall.
The second part is the back cut, or felling cut, which is made on the opposite side of the tree, parallel to the horizontal cut of the notch. This cut must be positioned slightly higher than the horizontal notch cut, usually by about one to two inches, to prevent the tree from sliding backward off the stump. The back cut is advanced toward the notch while leaving a section of wood in between, which is the hinge.
The hinge wood is the mechanism that guides the tree and controls the descent, and it should be approximately one-tenth of the tree’s diameter in thickness. Maintaining this intact hinge until the tree is committed to falling is crucial for safety and accuracy. As the back cut nears completion, felling wedges can be inserted into the cut to help push the tree over and prevent the saw bar from pinching. Once the tree begins to move, the operator must immediately disengage the throttle and retreat along the pre-planned escape route.
Limbing and Bucking the Trunk
After the tree is safely on the ground, the process transitions to limbing, which is the removal of branches, followed by bucking, which is cross-cutting the trunk into usable lengths. Limbing should generally proceed from the base of the tree toward the top, with the operator standing on the uphill side of the trunk whenever possible. It is important to work in a way that uses the trunk as a barrier between the saw and the operator’s body.
During both limbing and bucking, understanding the internal forces of wood—tension and compression—is necessary to prevent the saw bar from pinching. When a log is supported at both ends, the top side is under compression and the bottom side is under tension. Cutting into the compression side first causes the cut to close and pinch the saw bar.
To safely buck a log that is supported only at the ends, a small cut should first be made on the compression side (the top) to relieve some pressure. The main cut is then finished from the tension side (the bottom) to allow the cut to open as the log settles. Conversely, if a log is suspended with one end hanging free, the top is under tension and the bottom is under compression. In this case, the cut should be started from the tension side (the top) and finished from the compression side (the bottom), carefully watching the kerf to ensure the saw does not get bound.
Managing Dangerous Tree Situations
Certain conditions present specialized risks that require unique handling techniques.
Hung Trees and Widowmakers
A “hung tree,” or lodged tree, occurs when the felled tree fails to reach the ground and is caught in the branches of another standing tree. The absolute rule is never to cut the hinge or the supporting tree, as this can cause the lodged tree to fall unpredictably or swing violently toward the operator. If a tree becomes lodged, the safest course of action is to use mechanical aids, such as a winch, to pull the tree down from a safe distance. “Widowmakers” are detached or broken branches lodged high in a tree that can fall unexpectedly, posing a serious threat. These overhead hazards must be identified and addressed before any cutting begins.
Spring Poles
A spring pole is a small tree or limb bent under extreme tension by a fallen tree or other weight. If cut haphazardly, a spring pole can snap back with explosive force. To safely release a spring pole, the point of maximum tension must be identified, often by visualizing a 45-degree angle from the base of the bend. The tension is released gradually by making a series of small, shallow shave cuts into the compression wood on the side opposite the tension. This slow, deliberate process allows the wood fibers to break and the tension to dissipate safely, preventing a sudden, violent release.