How to Fell a Dead or Rotten Tree

Tree felling is extremely dangerous work that can easily turn deadly with even small errors. Within the dangerous art of tree felling, there is one task with a danger that shines above the rest: felling a dead or rotten tree. Trees are non-uniform, and their behavior when falling can be unpredictable. It is the task of the feller to make that fall as uniform and predictable as possible despite any irregularities. When felling a tree that is unsound, however, the unpredictability is amplified, and nothing can be taken as a given. Careful strategic planning is an absolute necessity, and even then, the danger is far from eliminated. In this article, we will discuss the best practices, strategy, and technique to fell a dead or rotten tree, but be warned: This is EXTREMELY dangerous. If you don’t feel confident in your ability to fell a tree safely, contact a professional.

1. Carefully Assess the Situation

The first step in felling a dead or rotten tree is carefully assessing the situation and any risk factors. While this is the first step of felling any tree, more time, attention, and observation must be given to dead and rotting trees.

Determine the Extent of Rot

First, determine the extent to which the tree is rotten, which is the greatest risk factor. Remember, there is a difference between dead trees and rotten trees. A tree that is freshly dead may be completely sound and present little risk, particularly if it died as a result of insect defoliation, drought, or similar condition. Afterall, our homes are soundly built with the wood of freshly dead trees. Conversely, trees that have full crowns may have extensive rot, particularly in the butt of the tree.

To check for rot, first look for obvious external signs, such as holes, mushrooms and conks, heavy woodpecker damage, and missing or loose bark. Any of these qualities can be indicators of rot, though not necessarily. In holes or areas of missing bark, use your fingers to press on exposed wood and take note of its physical characteristics. Is it soft to the touch? Does it feel spongey? Is it water-logged? A yes to any of these questions indicates extensive rot. Tapping the tree with the back of an axe can also give auditory clues to how rotten the wood is, but where a hard hat, as tapping an extensively rotten tree can cause branches to dislodge

Once the extent of rot is estimated, pay careful attention to the entirety of the tree and assess how far up the rot reaches. The higher the signs of rot go, the higher the rot reaches in the tree and the more danger and unpredictability felling the tree will present. In particular, pay attention to conks and the condition of the bark. On most species, separation in the crown is a good indicator of extensive rot throughout the tree.

Understand that it may not be possible to observe rot extent from the outside.

Assess Potential Felling Behavior

Once you have an idea of the extent of rot, you can make a more educated assessment of likely felling behavior. Begin by asking the following questions:

• Is the tree leaning? Is the lean great enough to break the tree or pinch my saw if I attempt to cut a notch, given the extent of the tree’s rot?
• How stable is the crown? Is debris such as bark or branches liable to fall down on me as I cut?
• Are there nearby trees? Is the tree likely to break in half if it comes in contact with these trees on the way down?
• Is there enough sound material to create a safe and dependable hinge on my cut?

If your answer to any of these questions indicates excessive risk in felling the tree, it is best left to the professionals. If you determine the tree can be safely cut, however, it is time to strategize.

Acknowledge the Unknown

While careful assessment is life-saving when felling a rotten tree, one has to acknowledge the limitations of one’s observation. Take the time to brainstorm what factors may be unknown or unknowable to you and the risks they might present. Taking the time to explore the limits of your knowledge is crucial, but don’t take my word for it:

There are known unknowns. That is to say, there are things that we now know we don’t know. But there are also unknown unknowns. There are things we do not know we don’t know.

Donald Rumsfeld on Tree Felling (Probably)

2. Determine a Plan and Strategy for Felling

Based strongly on your structural assessment of the tree and determination of present risk factors, it is time to develop a plan and strategy to fell the tree while mitigating identified risks.

When you fell dead and rotten trees, the goal should always be to eliminate unpredictability and bring the tree to the ground safely in an anticipated manner. This is the endgame of any plan.

Felling Direction and Notch Location

As with any tree, you must carefully determine the direction of felling, but unlike with most trees, you may not have much of a choice. You have to work with the conditions of the tree.

If the tree is leaning, you should always fell in the direction of the lean or as close to it as conditions allow. Trees with extensive rot are difficult if not impossible to wedge (sometimes it is dangerous to do so), and working against the forces of gravity introduces another element of unpredictability. Fighting the tree is hard enough. There is no need to fight gravity. If the direction of lean poses risk to property, hire a professional.

One must also base the direction of felling on where one can feasibly create the notch. Because the hinge must have as much sound material as possible, the notch is best placed on the side with the most sound material. Remember that the hinge has two dimmensions, length and width. Because dead wood is usually brittle, it is often preferable to make the wood longer and thinner than wider and shorter, if possible.

Take a look at the diagrams below to see how rot can affect the strategy of a cut.

In this example, we have a clear example of butt rot in a living tree that extends a good way up the stem. Because the tree is living, there is sound wood in the tree, and we have to utilize it to the highest degree. Unfortunately, forward lean limits the directions toward which this tree can be feasibly felled. There is also a decent amount of butt or root flare toward the bottom, which gives us an ample supply of sound wood.

Therefore, the best course of action is to place the hinge far enough into the tree to maximize hinge length (deeper cuts generally create longer hinges) and low enough to utilize the extra material provided by butt flare.

Below is an example of felling a totally dead tree that requires a different strategy

In this situation, the tree is totally dead and deeply decayed. The wood is brittle, and there exists a high degree of unpredictability. Because of these factors, the best course of action is to set the notch high. Doing so allows us to cut the hinge without crouching, which provides more reaction time and agility in the event of emergency. Additionally, cutting the notch high potentially avoids cutting into butt rot that may be present near the bottom, giving us marginally sounder wood.

Prepare Your Escape Routes

Before you begin cutting, it is essential you cut pathways for you to escape quickly in the event something does not go as planned. In most cases, these are best made heading in 135 degree angles away from the direction of felling. In other words, not totally in the opposit direction, but 45 degrees from the opposite direction. However, other plans may be more preferable depending on the unique threats you have identified.

3. Make the Notch and Back Cut

After the planning is done, it is time cut the notch and back cut and let it fall. This is of course the most dangerous part of felling dead and rotten trees. Once more, the number one task is to minimize unpredictability, and so, in most cases, the best course of action is to bore cut the tree. This gives the feller the complete ability to properly set the hinge prior to felling and allows control over exactly when the tree falls. It also greatly reduces the probability of a barber chair. Overall, it is a much safer way of felling trees, especially dead and rotten ones.

However, if you have never bore cut a tree before, don’t start on a dead or rotten tree. It can be a tricky skill to master, and learning the skill on a dangerous tree is no way to begin.

Otherwise, utilize a traditional back cut, coming in from behind the notch, but be extremely vigilant. Listen for cracking, and keep your eyes open, occasionally checking the crown. As soon as the crown starts to move or you hear any cracking, get out of the way fast!

Be Careful!

While the strategies listed here are best practices, they will not keep you totally safe. Nothing can. Perhaps then, the most important safety tool is your own humility. Recognize your limitations and know when a tree is simply to dead or rotten to fell safely. Above all, keep your wits about you and be safe.