Tree felling is the controlled process of cutting down a standing tree so that it falls precisely in a predetermined direction. This highly skilled operation requires careful planning and execution to manage the immense forces involved. The goal is to separate the tree from its stump using an engineered break in the wood to guide the fall. This ensures safety and prevents damage to the surrounding area. Specific techniques and safety protocols must be followed due to the high-powered machinery and unpredictable natural forces involved.
Site Assessment and Planning
Before any cut is made, the feller must conduct a thorough assessment of the tree and the surrounding environment. This initial inspection determines the tree’s natural lean, which is the direction of its weight distribution. Identifying this lean is primary, as it indicates the path of least resistance and the most likely direction of an uncontrolled fall.
The entire drop zone, the area where the tree is intended to land, must be cleared of people, vehicles, and obstacles. This zone should extend at least one and a half times the total height of the tree to account for potential kickback or unexpected movement. The feller must also account for current wind speed and direction, as even a light breeze can influence the final path of the tree’s descent.
A failure to plan escape routes is a leading cause of felling accidents. Two separate paths must be cleared of all debris, brush, and tripping hazards before the saw is started. These routes should be positioned diagonally away from the planned fall line, typically at a 45-degree angle to the rear of the tree’s trunk. The feller must retreat along one of these prepared paths immediately after the final cut is completed.
Executing the Directional Cut
Safe, directional felling relies on a precise sequence of cuts that create a hinge to control the fall. The process begins with the directional notch, also known as the undercut, which is cut on the side facing the intended fall direction. This notch consists of a horizontal cut and an angled cut that meet to remove a wedge of wood. This wedge is commonly cut to a depth of 20 to 25 percent of the tree’s diameter.
The most effective design is the open-face notch, which utilizes an opening angle greater than 70 degrees. This wide angle ensures the hinge remains intact for a longer duration, providing maximum control over the tree’s descent. The notch’s apex acts as a sight line, allowing the feller to accurately aim the tree toward the designated drop zone.
The next component is the hinge, which is the uncut wood remaining between the notch and the final cut. This section functions like a mechanical hinge, guiding the tree’s fall and preventing the trunk from splitting vertically, an event known as a “barber chair.” The hinge length should be at least 80 percent of the tree’s diameter at breast height (DBH). Its thickness should be about 10 percent of the DBH to provide adequate holding power.
The final step is the back cut, or felling cut, which is made on the side opposite the notch, slightly above the horizontal plane of the notch’s base. This cut is made toward the hinge wood, but never through it, stopping to leave the pre-measured hinge intact. Felling wedges, made of plastic or aluminum, are often inserted into the back cut before completion. This prevents the saw from being pinched and helps push the tree over in the desired direction.
Essential Safety Gear and Procedures
The physical dangers of operating a chainsaw and felling a tree necessitate the use of specialized personal protective equipment (PPE). Head protection is mandatory, typically a hard hat equipped with an integrated mesh face shield and hearing protection. Safety glasses should always be worn beneath the face shield for redundant eye protection against flying debris.
The lower body is protected by cut-resistant chainsaw chaps or trousers, which contain layers of woven material designed to snag and stop a moving chain upon contact. Foot protection is provided by sturdy, steel-toed boots with non-skid soles to ensure stable footing on uneven terrain. Heavy-duty work gloves also provide grip and protection for the hands.
Chainsaw operation requires adherence to specific safety rules. These include starting the saw on the ground and ensuring the chain brake is engaged before starting the engine. The saw must always be operated with a firm, two-hand grip to maintain control against the significant forces of the rotating chain. Due to the high-risk nature of felling, a strict procedure is to never work alone, ensuring a second person is available to assist or call for emergency help.