WORKING TECHNIQUES
English
–
27
Felling technique for tree tops
Safe distance
During tree maintenance work above ground level, the
working area must always be secured and marked out
with signs, tape or the like. The safe distance between the
top of the tree that is to be felled and the nearest
workplace must be at least 2 1/2 times the height of the
tree. Make sure that no-one else is in this risk zone before
or during felling.
Felling direction
The aim is to fell the tree in a position where you can limb
and cross-cut the log as easily as possible. You want it to fall
in a location where you can stand and move about safely.
The main thing to avoid is that the falling tree top should get
jammed in another tree. Taking down a ”jammed” tree top is
very dangerous (see point 4 in this section).
Once you have decided which way you want the top of the
tree to fall you must assess which way the top of the tree
would fall naturally.
Several factors affect this:
•
Lean of the tree
•
Bend
•
Wind direction
•
Arrangement of branches
•
Weight of snow
You may find you are forced to let the tree-top fall in its
natural direction because it is impossible or dangerous to
try to make it fall in the direction you first intended.
Another very important factor, which does not affect the
felling direction but does affect your safety, is to make sure
the tree has no damaged or dead branches that might
break off and hit you during felling.
Topping a tree
Topping a tree is done using three cuts. First you make
the directional cuts, which consist of the top cut and the
bottom cut, then you finish with the felling cut. By placing
these cuts correctly you can control the felling direction
very accurately.
Directional cuts
To make the directional cuts you begin with the top cut. Try
to take your position in the tree on the right side and cut
on the pull stroke.
Next make the bottom cut so that it finishes exactly at the
end of the top cut.
The directional cuts should run 1/4 of the diameter
through the trunk and the angle between the top cut and
bottom cut should be 45
°
.
The line where the two cuts meet is called the directional
cut line. This line should be perfectly horizontal and at
right angles (90
°
) to the chosen felling direction.
!
WARNING! It takes a lot of experience to
fell a tree. Inexperienced users of chain
saws should not fell trees. Do not
attempt any task beyond your experience
level!
!
WARNING! During critical felling
operations, hearing protectors should be
lifted immediately when sawing is
completed so that sounds and warning
signals can be heard.
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