6. June 2017- blog.stihl.com
A cry of “Timber!” resounds through the park. A 170-year-old beech tree, whose trunk has an impressive diameter of 120 centimetres, falls to the ground. Everyone is happy; the planning has paid off. Felling a tree this large is by no means an everyday occurrence, as the beech tree is not just tall – it also weighs several tonnes. Thus felling poses a real challenge, even for the experts.
STIHL did not want to let this chance slip by and was on site with three staff members, actively supporting the arborists’ efforts. They brought with them five high-performing chainsaws to ensure that they were well equipped for every situation: in addition to the felling, a Norway maple also needed to be heavily pruned. To do so, a cherry picker lifted the arborists 20 m in the air so that they could work on the tree’s crown.
The backdrop to this mission was Hohenheim Castle park in southern Germany.
A photographer captured this spectacular mission in images and we have reported on the most exciting moments for you.
Early morning: preparing for the felling
In the early morning before the tree felling: the beech tree (centre) and the Norway maple (beside it on the left) are still standing.
At the castle park in the early morning: On the morning of the tree felling, the 170-year-old beech tree is still standing. It is afflicted by a giant polypore. This kind of fungus usually appears on the tree’s trunk or roots and poses a risk to the tree’s stability.
To the left of the beech tree is the Norway maple, on which damage was also identified during a tree assessment. The maple has been particularly afflicted by large cavities in the trunk area. Because this tree was in the lee of the beech tree until now, its crown requires significant pruning in order to ensure the tree’s stability. As a result both trees are a hazard for visitors to the castle grounds.
Preparing the chainsaws for the tree felling.
Preparations are taking shape: On the day of the mission, a total of nine people are required on site to carry out the tree felling – including three experienced arborists and three STIHL experts.
But before the work can begin, all of the STIHL chainsaws need to be prepared. Sharpening the saw chains and filling the chainsaws with chain oil and fuel take top priority.
Overall, the tree maintenance experts have brought five chainsaws with them in order to ensure that they are prepared for any situation – including the STIHL MS 201 T arborist chainsaw [link to detailed product page] for smaller tree maintenance jobs in the cherry picker and the STIHL MS 880 heavy-duty chainsaw [link to product page] for crosscutting the trunk.
Morning: tree maintenance begins
The arborists prune the branches and twigs of the Norway maple using the MS 201 T.
Pruning the Norway maple: Standing a proud 24 metres tall, the Norway maple soars into the sky. For this reason, a cherry picker is required to expertly prune its crown. The arborist trims the smaller branches from the work platform using a STIHL MS 201 TC-M. For thicker branches, a STIHL MS 661 C-M [link to detailed product page] is put into action. By pruning the tree down to about nine metres, the arborists restore the tree’s stability.
The trunk remains standing in the castle grounds as a biotope that provides a habitat to native animals.
After working with the cherry picker, a tractor collects the branches that have been sawn off.
Back on the ground: After trimming the crown, a tractor collects the branches and twigs in order to clear the site for the felling of the beech tree.
Afternoon: felling the beech tree
Safety first! The direction that the beech tree falls in is additionally controlled by using a rope.
Fun at work: The beech tree that is afflicted by the giant polypore has a diameter of 120 centimetres and a full crown. An especially large area needs to be secured for the landing zone, as the tree has never been pruned before. This requires a lot of planning and comprehensive safety measures must be taken. The arborists attach a rope to the tree in order to better control the direction in which the beech tree will land. The other end is attached to a tractor. This allows the arborists to maintain the direction the tree falls in, even if its weight is distributed unfavourably.
Sawing out the felling notch.
A huge tree: After securing the area, the professionals take to the saw once again. First they saw out a felling notch, which determines the direction in which the beech tree will fall. But a simple V-shaped cut is not enough for a trunk diameter of over one metre. The experts decide to go for a heart-shaped cut (see photo on the right). This reduces the risk that the centre of the trunk will tear open and ensures that all of the wooden fibres will be severed.
The last work steps. After the felling cut has been made, the only thing preventing the tree from falling to the ground is the retaining strap.
The utmost concentration: In order to ensure that the tree trunk does not fully sever and fall down before it is supposed to, the felling cut is first marked on the tree trunk using crosses. However, the utmost concentration is required when laying out the last cuts, as all that will be holding the beech tree together afterwards will be a retaining strap a couple of centimetres thick. A STIHL MS 661 C-M is used [link to product page].
The beech tree falls to the ground once the retaining strap has been severed.
Watch out – timber! Slowly at first, and then with increasing speed, the beech tree falls and then hits the ground. It falls into the intended landing zone as planned. The tree maintenance experts are satisfied. But their work is not over yet: they still need to chop the beech tree.
As a result of the impact, the tree has been broken in a number of places.
Chopping the tree trunk: The beech tree’s heavy weight and its hard impact with the ground have led to a number of breaks in the wood. But these break points are not enough: in order to prepare the massive beech tree trunk for its removal, the experts need to cut it up even further using a chainsaw. They expertly buck the tree trunk and remove its branches.
The massive beech tree is cut up using a STIHL MS 880.
The splinters fly: Because of the trunk’s large diameter, a STIHL MS 880 is used to chop the trunk and cut up the stump.
In the evening: removing the wood
A tractor is used to remove the beech tree’s stump.
Transporting a heavy weight: After successfully cutting up the tree, the park site has to be cleared. A tractor is used to remove the upper part of the stump. Wedges have been sawn into the stump so that the tractor’s claw can get a better grip. Nevertheless weighing in at an estimated one tonne, the stump pushes the hauler to its limits.
The castle park on the evening of the tree felling. The beech tree has been felled and the Norway maple has been pruned as planned.
A busy day draws to a close: Here you can see the results of the tree felling mission after the area has been cleaned up. The beech tree has been successfully felled. Further to the left of the image, you can see the heavily pruned Norway maple.