Winching is a specialized procedure for safely felling trees that are leaning heavily or are hung-up after a failed cut. This method applies mechanical advantage to manipulate the tree’s direction of fall, counteracting a dangerous natural lean or poor weight distribution. Executing this technique requires careful pre-planning and the use of engineered equipment to manage the substantial forces involved. Winching significantly reduces the risks associated with simply cutting a compromised tree, which could otherwise fall unpredictably or split catastrophically.
Site Assessment and Hazard Mitigation
Before any equipment is deployed, a comprehensive evaluation of the work site and the tree must be completed. Determining the tree’s center of gravity and the degree of its lean informs the required pulling force and the angle of the winch line. The target drop zone needs to be cleared of people and obstacles, ensuring the tree has a clear path for its descent. This assessment helps in approximating the load weight necessary to select the correct gear.
A thorough search for overhead power lines or nearby structures that could be contacted during the fall is essential. Establishing multiple clear escape routes is a fundamental safety measure, and these paths must lead away from the line of tension and the predicted path of the falling tree. The pulling force needed is a function of the tree’s diameter, height, and the severity of its lean, which influences the size of the equipment selected. Professionals often select gear with a pull capacity that significantly exceeds the estimated requirement to ensure operational safety.
Selecting and Anchoring the Winching Gear
The selection of the winch depends on the tree’s size and the necessary pulling force, with options ranging from manual hand winches to electric or gas-powered units. The winch must have an adequate weight rating for the task, and it is best practice to choose one with a capacity exceeding the calculated load. The winch cable itself should be a high-strength, low-stretch material, such as steel wire rope or specialized synthetic line, to ensure a predictable and controlled application of force.
Rigging components include wide tree straps, or tree savers, which protect the bark of the anchor tree from damage. Snatch blocks, or pulleys, are used to redirect the pull around obstacles or to multiply the winch’s pulling power through mechanical advantage. For example, a single pulley system effectively doubles the force applied, allowing a smaller winch to manage a larger load.
A solid anchor point is typically another large, healthy, stationary tree or a robust ground anchor designed for high-tension work. When using an anchor tree, the strap should be positioned as low as practical to minimize leverage and reduce the risk of failure. The entire rigging system, including all shackles, straps, and connection points, must be inspected to ensure the safe working load of every component is compatible with the maximum potential force generated by the winch.
Coordinated Cutting and Controlled Descent
The winch cable must be attached high on the leaning tree’s trunk, ideally above its center of gravity, to maximize leverage and felling force. Attachment often involves using a throw weight and rigging line to hoist the winch cable or strap into position. Once secured, a slight initial tension is applied to the line, removing slack and ensuring the system is ready to pull immediately upon completion of the saw cuts.
The cutting sequence begins with the face notch, or directional cut, which determines the exact direction of the fall and establishes the hinge wood. For a severely leaning tree, the specialized bore cut technique is employed for the back cut. This involves inserting the saw bar into the trunk to remove wood while intentionally leaving the corners intact. This method maintains a secure hinge and prevents a dangerous vertical split, known as a “barber chair,” which occurs when the tree’s weight prematurely rips the wood upwards.
With the hinge wood prepared and the bore cut completed, the final remaining wood is severed, and the winch operator immediately applies full tension to pull the tree over. As the tree begins to move, the chainsaw operator must swiftly retreat along one of the predetermined escape routes, moving away from the falling tree and the tension line. Tension on the winch must be maintained continuously until the tree is fully on the ground, ensuring the descent remains controlled.