Last Updated on February 21, 2022 by Grow with Bovees
The Best Types of Tree Felling Cuts for Safe Tree Removal
Many people make the unfortunate mistake of assuming that felling a tree is easy.
You just get out your chainsaw, cut through the trunk and it falls over.
Simple, right?
Wrong!
When you have a tree that needs to be felled, you must plan it out so that the tree falls safely and in a straight line, avoiding damage to nearby property or causing serious injury to yourself or bystanders.
Making the right type of cut, in the right place will make the difference between a successful, problem-free job and a disaster.
Felling Trees Safely
Falling trees are dangerous.
If you don’t take the proper precautions things can go badly wrong very quickly.
The following article is an informational guide for smaller trees up to 20 inches in diameter and if you are inexperienced, you should always consult a professional for advice before attempting any work.
Felling larger trees is a job for a professional tradesperson and we do not recommend you attempt these yourself.
The very first thing you need to do before even firing up your chainsaw is to survey the job and make sure you have all the correct safety equipment.
You need to look at how old the tree is, what buildings, power lines, or other trees are around it, whether it’s leaning a certain way, tree lengths, how dense the wood fibers are and where the branches are.
Weather conditions are important as well of course so choose a dry day with little or no wind. If the tree crown is swaying at all in the breeze, put the tools away and pick another day.
It’s also important to check that there are no dead branches or a lodged tree caught up in the higher branches, these can be very dangerous if they fall whilst you’re working.
Look for signs of rot in the tree trunk before beginning to cut as well. If the tree is dead, or has a decayed or rotten core, it will not behave in the same way as a healthy tree and is best left to a professional arborist.
Once you’ve surveyed the area, taken note of adjacent trees and buildings, and planned your escape routes, it’s time to plan the type of tree felling cut or notch you’re going to make.
Why Cut a Notch in the Tree at all?
By removing a small piece of wood and creating a hinge, you are making sure the tree falls in the direction you’ve chosen to avoid overhead lines, buildings, etc., and ensuring your escape route to a safe distance is not compromised.
Without cutting a notch, even a perfectly straight tree with no leaning or heaviness on one side could fall in any direction. A well-chosen directional cut and hinge not only helps the tree fall where you want it, but it also makes the whole job much safer too.
What Are the Different Types of Tree Felling Cuts and Notches?
There are three types of basic cut you will use to fell a tree:
Top Cut
This is the first cut you will make and is the cut used to make the top of the notch.
Undercut or Bottom Cut
This is the second cut you will make and is used to cut the lower face of the notch.
Back Cut or Felling Cut
This cut is made on the opposite side to the notch and is usually a horizontal cut at or slightly above the apex of the notch.
There are 3 main types of notch; open-faced, conventional, or a Humboldt notch.
Of these the open-faced notch is the most common type of cut, it’s also the easiest to do, especially with larger trees.
Open-Faced Directional Notch
Pros – Most accurate notch. The hinge will remain intact until the tree is almost completely down.
Cons – Can leave a fairly large stump behind.
The best choice for trees on slopes and when you want the hinge to stay intact as the tree falls. This notch allows for the most control of falling direction and is created by cutting a large opening that has an angle of between 70 and 90 degrees, with the bottom cut angled away from the top and felling cuts.
Conventional Directional Notch
Pros – Good for split-prone trees. Leaves behind a low stump height.
Cons – Smaller angle of notch can result in the hinge breaking and kicking back before the tree has completely fallen.
The oldest and most traditional notch that allows for quick removal whilst still retaining a high degree of accuracy. Notch is usually cut at an angle of between 45-55 degrees. Often used for felling medium and tall sized trees on flat, level ground.
Humboldt Directional Notch
Pros – Leaves a low stump height, especially on steeply sloping terrain.
Cons – On flat ground leaves a higher stump height. The hinge may also break before the tree is completely down.
Best for very tall trees on steep slopes as well as types of trees that tend to split when being felled. Usually has a notch opening angle of a minimum of 45 degrees.
Using a Chainsaw to Cut a Notch and Hinge
The conventional notch came about when the only tools available for cutting down trees were the humble saw and felling axe. Nowadays most professional loggers will use a chainsaw to create directional notches and back cuts.
No matter which notch you use, stop and remove the chainsaw once the tree starts falling, and walk quickly away down one of your escape paths, keeping your eye on it to make sure it doesn’t twist or change direction.
Open-Faced Directional Notch
First of all, remove the bark and protrusions from the area where you intend to make your directional felling cuts.
Mark the stump height at around shoulder level when kneeling down next to the tree.
Decide which direction you want the tree to fall and make a felling mark to show where your top cut will start.
Make your top cut downwards towards the stump height mark at an angle of approximately 70 degrees and stop when you have reached 25% of the diameter of the tree.
For the undercut, cut upwards at a 20-degree angle towards the end of the top cut. Stop when you reach the other cut and remove the wedge of wood leaving an open face with around a 90-degree notch opening.
Now locate the point on the opposite side of the tree that is either level with or just above the notch angle and mark where your back cut will start.
Proceed to cut horizontally toward the notch, stopping when you have a hinge of around 1/10th of the trunk diameter left.
Conventional Felling Notch
Again, first of all, cut out any root protrusions at the base of the tree and remove the bark from the area where you need to make your cuts.
As with the open-faced notch, mark the height of the desired stump with your chainsaw.
Make a felling mark for the top cut to start so that the tree will fall in the desired direction.
With the chainsaw at full throttle, cut down at an angle of 60-80 degrees towards the stump height mark until you are approx 1/4 the way through the trunk.
Next, make a horizontal undercut or bottom cut to meet up with the top cut and no further.
Remove the chunk of wood.
Finally, make the felling cut from the opposite side of the tree in line or slightly above the undercut, leaving a hinge of around 10% of the tree diameter.
Humboldt Notch
As with the other notch types, clear the base of the tree of any root protrusions and remove the bark from where you will be making cuts.
Decide on your stump height and mark this on the trunk.
Make a felling mark on the tree in the direction you want the tree to fall.
With the chainsaw at full throttle, use this mark as a starting point to make a horizontal top cut into the tree at the stump height. Stop when the cut is about 25% of the tree’s diameter.
Now create the Humboldt cut by making an undercut up towards the top cut at a 45-degree angle, stopping when you reach the other cut.
Knock out the piece of wood and mark the start of the back cut 1 inch above the angle of the Humboldt cut on the opposite side of the tree.
Cut in horizontally towards the notch, stopping at a point that leaves roughly 1/10th of the tree diameter as a hinge.
Tree Felling Techniques Conclusion
Whichever notch type you prefer to work with, whether it’s the Humboldt notch, Open-Faced Notch or the traditional Conventional Notch, working safely and with the correct tools will make all the difference.
Safe, basic tree felling relies on planning out the falling tree boundary, looking out for adjacent trees and buildings, using the correct felling notch, and watching out for hung-up trees once the felling is completed.
Inexperienced tree cutters should avoid working on larger diameter trees, dead trees or mature tree trunks that are leaning.
So, be aware of the various types of tree felling cuts, follow basic safety rules, wear protective equipment and observe chainsaw safety at all times.
Resources;
https://extension.missouri.edu/publications/g1958
https://sciencing.com/advanced-tree-felling-techniques-8611141.html
