ICFR – Chainsaw Safety and Operating Handbook
18
•
Complete the directional notch and felling cut,
ensuring that the tree is on the ground before
commencing to fell the next tree. Only single tree
felling is permitted (no domino felling). Hang-ups
and cut-up trees must be dealt with as described
in sections 10.12 and 10.14.
•
Do not stand on the downhill side of the tree when
felling trees on slopes.
•
Do not complete the felling cut on the side towards
which the tree is leaning.
•
Ensure the required felling aids are at hand and
used if required.
•
Prepare for felling as described in section 10.9.
It is recommended that the chainsaw operator gives timely
and adequate audible warning prior to completing the
felling cut. Audible warning is not required if the operator
has an unobscured view of the entire area which could be
affected by the tree being felled and is assured that there
is no-one within the area.
10.6
f
elling
AidS
10.6.1
p
urpoSe
The primary purpose of felling aids is to:
•
Hold the tree upright.
•
Assist in directional felling.
•
Alter tree balance and weight distribution.
•
Keep saw cuts open and thus decrease the
possibility of the guide bar being pinched.
The main felling aids used in South Africa are felling
levers and wedges.
10.6.2
f
elling
leVerS
The felling lever is commonly used when felling
smaller trees in clearfelling but is vital in thinning
operations. There are various models with varying
handle lengths.
When using felling levers:
•
Remove the bark where the felling lever will be
inserted so as to ensure sufficient leverage.
•
Ensure that the felling lever is placed as deep
as possible in the felling cut in order to achieve
maximum leverage.
•
Lift with the legs, keep the back straight.
Refer to section 10.11.2.3 for the technique using
felling levers.
A felling lever with a hook can also be used as a
canthook to roll trees or logs. It also has the added
advantage that it can be used in taking down hang-ups.
(Refer to section 10.12).
Photo 7: Felling levers
10.6.3
f
elling
wedgeS
Felling larger trees may require the use of wedges.
Felling wedges can be made of different materials,
e.g. wood, plastic, light metal or steel. Do not use steel
wedges when felling small diameter trees as chain
damage could occur. Steel wedges can be used on large
trees as the probability of chain contact is less likely.
Refer to section 10.11.3 for techniques using wedges.
Depending on the size of the tree to be felled, different
sized wedges should be used. The wedge must be
placed in the felling cut before it is completed.
Photo 8 : Wedges