Husqvarna 570 EPA II Manuel D'utilisation page 27

All control over the felling direction is lost if the felling hinge is
too narrow or non-existent, or if the directional cuts and felling
cut are badly placed.
When the felling cut and directional cut are complete the tree
should start to fall by itself or with the aid of a felling wedge or
breaking bar.
We recommend that you use a bar that is longer than the
diameter of the tree, so that you can make the felling cut and
directional cuts with single cutting strokes. See instructions
under the heading Technical data section to find out which
lengths of bar are recommended for your saw.
There are methods for felling trees with a diameter larger than
the bar length. However these methods involve a much
greater risk that the kickback zone of the bar will come into
contact with the tree.
WORKING TECHNIQUES
Freeing a tree that has fallen badly
Freeing a "trapped tree"
It is very dangerous to remove a trapped tree and there is high
accident risk.
Never try to fell the tree that is trapped.
Never work in the risk zone of the hanging trapped tree.
The safest method is to use a winch.
• Tractor-mounted
• Portable
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Canadian