Common Tree Felling Accidents and What You Can Do to Prevent Them
Unfortunately, tree felling accidents are quite common.
Many videos of accidents are available on Youtube.
They are occasionally billed as humorous, but to anyone who values life and limb,
they are anything but funny.
Accidents do happen, but fortunately, use of professional protective equipment (PPE),
good technique, and attention to detail
can greatly reduce their occurrence and the injuries they cause.
The importance of PPE can never be overstated.
Head, ear, eye, leg, and foot protection are mandatory.
A chainsaw should never, under any circumstances, be operated without them.
A good pair of gloves is also strongly recommended.
Handling a saw without PPE
reflects poorly on the individual, the management, and the company.
It also violates OSHA and ANSI regulations.
No excuse for failure to use PPE is acceptable.
Probably the most common cause of accidents is kickback.
Kickback occurs when the top quarter of the saw blade, also known as the kickback zone,
contacts a solid object (wood or metal).
Because the chain is coming down the edge of the saw bar in the kickback zone,
the depth gauge is lower than it should be in relation to the tooth.
Literally, the saw bites off more than it can chew, stopping or slowing the chain.
The result is a rotational force that flings the bar backward, into the operator.
Kickback can also happen when the bar is pinched by the tree being cut (pinch kickback).
If the chain is pinched on the top of the bar, the saw will be pushed back into the operator,
if it is pinched on the bottom of the bar, the reaction pulls the saw forward
and can cause the operator to fall on the saw.
What can you do to prevent Kickback?
Hold the saw with both hands, thumbs securely wrapped.
Have one hand on the rear handle and the other on the front handle.
Ensure that you have firm footing before starting to saw.
Stand to the side of the cutting path of the chainsaw.
Position yourself so that you are not near the bar and chain when the saw is running.
Know where the bar tip is at all times.
Do not let it touch logs, branches, or the ground when the saw is running.
Cut only one piece of wood at a time, never two branches at once.
Run the saw at full power when cutting to help prevent pinch kickback.
The barber chair occurs when the force pulling forward on the trunk is great enough to split
the trunk but not great enough to trigger the hinge to fold.
It is often caused by heavy front leaning trees.
It can also occur by applying too much force to a rope while pulling the tree over using
The bottom of the tree goes up and the top comes down (like a barber chair, feet up,
Workers can be struck by the trunk as it swings up or crushed as it falls.
What can you do to prevent being struck by a barber chair?
Have your escape route planned in advance.
It should be away from the tree at a 45-degree angle from the direction of the tree fall.
Make sure the escape route is cleared.
Change the direction of felling to avoid excessive forward lean.
Take care with your felling cuts and regardless of the type of notch you cut,
correct any undercutting or bypassing before making the back-cut or bore-cut.
Make sure the chain is sharp, and the saw is running properly,
this will decrease the time the wood is under tension.
An open-faced notch, followed by a bore cut through the tree to create the hinge reduces
the chance of getting hurt by a barber chair.
Using this technique, tree fibers in the trunk are less likely to be pulled to the breaking point.
Other techniques require the operator to be standing at the tree, sawing through
more of the hinge as the tree begins to fall.
This puts the operator in a very dangerous position,
right behind the tree should a barber chair happen.
Entanglement is when a tree being felled strikes branches or the trunk of another tree.
It changes the direction of fall or hangs up the tree, leaving a dangerous overhead hazard.
The best solution to entanglement is avoidance.
It can be avoided by implementing the five step felling plan.
First, identify Height, Hazards, and Lean.
Then make sure you have the needed equipment.
Plan and clear your escape route.
Cut the notch in the tree and finally, make bore or back cut and use the escape route.
If a tree is hung-up in another tree the best option is to pull it out with ropes.
Others techniques should only be implemented by very experienced professionals.
In storms, trees may become entangled in utility lines.
In this case, do nothing, wait for the utility company to arrive and declare the situation
safe before attempting to free the tree.
Setback occurs when the tree sets back during the bore cut or back cut, pinching the chainsaw.
In extreme cases, the tree may fall back onto the feller.
Setback occurs when a tree has back lean.
Once again, application of the five step felling plan will prevent setback.
Lean should be identified prior to making any cuts.
If the tree has back lean, you will need either wedges or rope.
Remember, if you don't have the equipment on hand and in working order, do not cut the tree.
Putting a wedge in any tree you are felling is good practice and will prevent setback.
Stump jump occurs when the hinge fails, and the tree detaches from the stump.
At this point, the tree is in free fall and completely out of control.
The tree can jump onto the feller or the tree trunk can strike the feller.
The hinge can fail when the notch is too deep, the angle of the notch is 45 degrees or less,
or the back cut is too high.
This accident is much less likely if an open-faced notch (70-90 degrees) and a bore cut are used.
Once again your best protection is the rigorous application of the five step felling plan.
The escape route should be identified and cleared prior to cutting.
When the tree begins to move, the workers should be moving along the escape route
and nowhere near the detached tree.
Wood under tension is always potentially dangerous.
A relatively small branch or trunk can cause great damage.
A spring pole is when a tree or branch is under great tension and the chainsaw operator
cuts into the wood, resulting in a violent release of energy.
The operator may be struck by the trunk, limb, or chainsaw.
This generally occurs during limbing and bucking but not exclusively,
it can also occur up in the canopy with storm damage.
A tree or branch with a bow or sweep will store energy, ready to be released upon cutting.
There are two cutting methods that will safely release the tension in a spring pole.
First, identify the compression and tension side of the wood.
Never cut on the tension side.
Next, look for the point of maximum tension.
Mentally, draw a line along the trunk of the tree and a line at a right angle from the
top of the bow to the trunkline.
Bisect those lines with another line at a 45-degree angle.
That is the point of maximum tension.
The accordion cut is a series of small relief cuts made on the compression side of the tree
opposite from the point of maximum tension.
This can be a handy cut for short people because it is done under the branch.
The shave cut will also release the tension.
This is also made at the point of maximum tension.
One layer is shaved off at a time until the branch relaxes, releasing all tension.
We've covered the most common accidents that can occur during tree removal, but this list
of accidents is not all-inclusive.
Your best defense is training, education, and a keen awareness of your surroundings.
Cut smart, cut safe!