Fallen trees present a unique and dangerous challenge, requiring an approach distinctly different from felling a standing tree. The immense weight and unpredictable resting points of a downed trunk create powerful, unseen forces that can cause wood to snap, violently spring back, or bind a chainsaw blade instantly. Successfully dismantling a tree into manageable sections requires a deliberate, safety-first methodology built on careful assessment and preparation, respecting the stored energy within the wood fibers.
Necessary Safety Gear and Saw Preparation
Before approaching a fallen tree, the operator must be equipped with appropriate Personal Protective Equipment (PPE) designed to mitigate the extreme risks of chainsaw operation. Head protection is paramount, requiring a hard hat with an integrated face shield to protect against falling debris and flying wood chips. Hearing protection, such as earmuffs or earplugs, is necessary to prevent hearing loss from the sustained high decibel levels of the running saw.
The lower body needs defense, provided by cut-resistant chaps or pants constructed with ballistic nylon fibers. These specialized fibers snag and instantly stop a moving chain upon contact, protecting the legs from deep lacerations. Heavy-duty work gloves improve grip and protect the hands, while steel-toed boots with robust ankle support provide stability and shield the feet from dropped logs or the saw itself.
Saw preparation is equally important for both safety and efficiency, starting with a functional check of the chain brake mechanism. The chain must be properly tensioned and sharpened, as a dull or loose chain increases operator fatigue and the likelihood of kickback. Always ensure the fuel tank and bar oil reservoir are topped off before beginning work, as running out of either mid-cut can be a hazardous interruption.
Understanding Tension and Compression in Wood
The most significant danger in cutting a fallen tree stems from the complex mechanical forces created by the log’s weight distribution: tension and compression. When a log is suspended between two points or bent over an obstruction, the wood fibers on the outside of the curve are stretched and under tension. Conversely, the fibers on the inside of the curve are being crushed together, placing them under compression.
Cutting into the tension side of the log first is extremely hazardous because the stored energy is released instantly, often resulting in the log violently snapping or whipping open. This sudden release can propel the wood toward the operator or cause the trunk to roll or shift unpredictably. In contrast, cutting into the compression side causes the kerf—the space created by the saw cut—to close rapidly, which will pinch the guide bar and bind the saw.
To safely navigate these opposing forces, the operator must first visually assess the log to determine where the bending or support points are located. A simple test involves making a shallow, partial cut into the log and observing whether the cut opens or closes; an opening cut indicates tension, while a closing cut confirms compression. The general rule is to always cut first on the compression side to create a stress-relieving notch.
Making the Relief Cut
This initial relief cut should penetrate about one-third of the log’s diameter, preventing the log from pinching the saw when the final cut is made. The final cut is then completed from the tension side, allowing the log to separate safely and controllably. Failing to identify these zones can lead to a saw being trapped or a log reacting with a sudden, forceful movement.
Techniques for Limbing and Bucking
The physical process of dismantling a fallen tree begins with limbing, which is the removal of all branches from the trunk. For stability, always work from the butt end (base) toward the top, standing on the side of the trunk opposite the branch you are cutting. This positioning places the log between you and the operating saw, providing a physical barrier in case of kickback or a sudden shift.
Avoid cutting any branch that is currently supporting the main trunk and holding it off the ground, as this could cause the entire log to drop or roll. Branches that are bent and under stress, often referred to as “spring poles,” must be approached with extreme caution, as they can whip back with considerable force when cut. These should be shaved down gradually from the compression side until the tension is safely released.
Once limbed, the trunk is prepared for bucking, the process of cutting the log into manageable lengths, which requires careful application of the tension and compression principles. When a log is fully supported on the ground, a single cut from the top, known as over-bucking, is usually sufficient. However, the saw must be stopped before hitting the dirt to prevent dulling the chain.
For logs resting entirely on the ground, a partial cut from the top, followed by rolling the log and finishing the cut from the opposite side, avoids damaging the saw blade. For logs supported at one or both ends, a two-cut system is necessary to prevent binding. First, make an under-bucking cut from the bottom, on the compression side, penetrating about one-third of the way through the log.
Then, finish the cut from the top, aligning the over-bucking cut with the initial notch to ensure a clean separation without the saw becoming pinched. For logs too large for the bar to cut through, wedges made of plastic or aluminum can be driven into the top cut to keep the kerf open and prevent the wood from binding the saw.