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Watch out for power lines and other people's property. If necessary, notify the power supply
company or the property owner.
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Judge the falling direction of the tree. Factors influencing the falling direction of the tree:
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Natural lean of the tree
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Height of the tree
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Branches growing on one side
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Level ground or slope
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Asymmetrical growth, wood damage
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Wind direction and wind speed
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Snow load
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When working on a slope, always work uphill of the tree to be felled.
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Establish your escape route in advance, and make sure that there are no obstacles in the
way. The escape route should be at an angle of approx. 45° backwards from the falling
direction (figure 17).
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The trunk must be free from growth, branches and foreign bodies (e.g. dirt, stones, loose
bark, nails, staples, wire, etc.).
Make two undercuts and one back cut in order to fell a tree.
1. During back cuts and cross-cuts, place the bumper spike firmly against the wood to be
cut.
2. Saw the first undercut (18/C) horizontally, then the second undercut at an angle of at
least 45° from above. This prevents the chain saw becoming trapped when you make the
second undercut. The undercut must be as close as possible to the ground and in the
required felling direction (18/E). The depth of the undercut should be about 1/4 of the
diameter of the trunk.
3. Cut the back cut (18/D) exactly horizontally opposite to the undercut. The back cut
must be made 3-5 cm above the horizontal undercut.
4. Saw in the back cut (18/D) sufficiently deep so that a bridge (18/F) of at least 1/10 the
trunk diameter remains between the undercut (18/C) and the back cut (18/D). This bridge
prevents the tree from twisting and falling in the wrong direction. The tree should start to fall
when the back cut (18/D) approaches the bridge (18/F).
If the tree falls whilst you are sawing:
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Interrupt the back cut if the tree does fall in the wrong direction or leans back and traps the
chain saw. To open the cut and fell the tree, drive in wedges in the direction of the required
felling line.
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Immediately pull the chain saw from the cut, switch it off and put it down.
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Walk away in the direction of the escape route.
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Watch out for falling branches and twigs.
5. If the tree remains standing, drive wedges into the back cut in order to cause it to fall in
a controlled way.
6. At the end of sawing work, immediately remove your ear defenders and listen out for
signals or warning calls.
