Notching undercut
Make the notch 1/3 the diameter of the tree, perpendicular to the direction of falls
as illustrated in Figure BB.102. Make the lower horizontal notching cut first. This
will help to avoid pinching either the saw chain or the guide bar when the second
notch is being made.
Felling back cut
Make the felling back cut at least 50 mm higher than the horizontal notching cut
as illustrated in Figure BB.102. Keep the felling back cut parallel to the horizontal
notching cut. Make the felling back cut so enough wood is left to act as a hinge.
The hinge wood keeps the tree from twisting and falling in the wrong direction. Do
not cut through the hinge.
As the felling gets close to the hinge, the tree should begin to fall. If there is any
chance that the tree may not fall in desired direction or it may rock back and bind
the saw chain, stop cutting before the felling back cut is complete and use
wedges of wood, plastic or aluminium to open the cut and drop the tree along the
desired line of fall.
When the tree begins to fall remove the chain saw from the cut, stop the motor,
put the chain saw down, then use the retreat path planned. Be alert for overhead
limbs falling and watch your footing.
Figure BB.102 – Description of felling: undercutting
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