Danger zone
A danger zone surrounds the tree to a distance of 2 1/2 times the height of the tree. See to it that no one is standing within this zone while you are felling the tree.
Felling direction
When felling a tree, one always aims to place it where neither objects nor difficult terrain will hamper limbing and cutting. Unobstructed movement and secure footing are essential.
It is also important to avoid lodging the tree against another tree. A lodged tree is extremely dangerous.
After determining where you want the tree to fall, you must also consider the likely unaided direction of fall. This is affected by the straightness and lean of the tree, wind direc- tion, concentration of branches and any snow that may weigh the tree down.
After assessing all these factors, you may find you have no choice but to fell the tree in its natural direction of fall because your preferred direction of fall is likely to fail.
Another important factor affecting your personal safety, though it has no bearing on the direction of fall, is the presence of any dead branches which could fall while you are felling the tree.
Clearing branches/Line of retreat
Remove any branches from around the base of the tree which may in-
terfere with your work. It is safest to work from the top down and to keep
the tree trunk between you and the running chain. Never cut branches
above shoulder height. Clear under- growth around the tree and identify
your line of retreat or escape, taking note of any obstructions (stones, branches, holes, etc.).Your line of retreat should be at an angle, around 135° behind the direction of fall.
Felling
Three cuts are made to fell a tree. The «TOP NOTCH CUT» and the «BOTTOM» or «HORIZONTAL NOTCH CUT» forms the «NOTCH», which determines the direction in which the tree will fall. The final cut is the «FELLING CUT», which allows the tree to topple over.
Notch
To form the NOTCH, start with the TOP NOTCH CUT. Using the bottom of the guide bar (pulling chain), make a 45° downward angled cut at right angles to the intended direction of fall.
Next do the BOTTOM NOTCH CUT, ensuring that it meets the bottom of the TOP NOTCH CUT precisely.
Notch depth should be around 1/4 of the diameter of the tree and the angle should be around 45°.
The line defined by the inside angle of the notch must be precisely horizontal and at a precise right angle to the direction of fall.
Felling cut
The felling cut is done from the opposite side of the tree and must also be horizontal. Stand with the tree to your left and cut with the bottom of the guide bar (pulling chain).
Place the FELLING CUT approximately
Cut at full motor speed, feeding the saw slowly into the tree. Watch out for tree movement opposite to the intended direc- tion of fall. Insert a WEDGE or FELLING BAR in the FELLING CUT as soon as the depth of the cut permits.
When complete, the FELLING CUT must be parallel to the notch and leave a strip of HINGE WOOD at least 1/10 the diameter of the tree.
The HINGE WOOD acts as a hinge, steering the direction of the falling tree.
If the HINGE WOOD is too small or has been sawn through, or if the
notch and the felling cut are mismatched, the tree is no
longer under control.
As the felling cut approaches the notch, the tree should start falling, either by itself or with the help of a WEDGE or
FELLING BAR.
ENGLISH
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