Over the decades, a beautiful mixed forest has grown up on the Hardtberg near the Helios Clinic. "The deciduous wood, especially oak and sweet chestnut, has a high level of vitality and makes a very healthy impression," says Ertelt. The pine trees around the almost 160 metre high Hardtberg hilltop are the problem child. Its umbrella-shaped crowns characterise the landscape, for example on the Venusberg.

More than 500 pine trees, around 80 years old, have been felled over an area of around 20 hectares. Around 1000 solid metres are now lying in piles several metres high, ready for collection. The freshly cut wood exudes the typical intense resin flavour. The trees were definitely diseased and dead, says Ertelt. Pines are considered robust and adaptable, so how can that be?

A number of unfavourable factors came together, says the district manager. The dry summers, climate change. Due to its location on a hilltop, the Hardtberg forest is not optimally supplied with groundwater anyway. The pine can actually cope with drought. "Only not for a long time and when the groundwater level is far below ground level. The roots of the pine are not designed for this, the tree dies and loses stability. For the sake of road safety for forest visitors, it is urgently necessary to remove these trees."

However, it is also dangerous for forestry workers to use a saw on dried trees. Trunks and branches break out of the crown unpredictably. "Machines such as harvesters and forwarders are therefore used to increase work safety. The aim of the measure is to ensure that visitors can safely enter and enjoy the forest on the paths again," emphasises Ertelt. He does not want to have to take the blame for a walker being hit by a broken branch.

"In any case, the Hardtberg forest will continue to be planted with pine trees," says the forester. "Provided the remaining pines defy climate change." After the thinning, there are still enough vital pines. "There's no question of clear-cutting. Even dead trees that would foreseeably not fall onto hiking trails in a storm, for example, were left standing to enrich the habitat." In addition, the company's motto is: "We never cut down more than will grow back.“

One special feature: the Hardtberg forest is owned by the federal government. As Ertelt explains, the "reserved area" is an expansion option for the Ministry of Defence on the Hardthöhe, which was never implemented. From today's perspective, a good thing. The Rhine-Weser Federal Forestry Organisation is responsible for the former and many of the areas used for military purposes in NRW. Ertelt's area of operation is part of the Wahner Heide - plus parts of the Hardtberg Forest. "The Federal Forestry Organisation has a wide variety of tasks," he says. And his job is to "shape forests“.

Ertelt believes it is a rumour that the federal government improves its budget by selling trees. "The economy is not the federal government's top priority". Firstly, the intention of the state forest is to "organise" the forest. And secondly: "Compared to the timber prices that are ultimately demanded on the construction market, we have to sell our logs." But there is another problem. The quality of the wood deteriorates when dead trees are harvested. Where, for example, you can normally expect 80 per cent of pine trees to be sawable, i.e. high-quality wood, in the Hardtberg forest it is now only 50 per cent.

If you look closely at the piles, i.e. the sorted, stacked logs, you can recognise the bad piles by their fraying and pest infestation. This is so-called industrial timber, which is shredded and pressed into chipboard. Whereas the sawable wood, cut into boards, is suitable for solid pieces of furniture, for example. After all, more is paid for this than for industrial timber. The Hardtberg forest will not save the federal budget.

The forest manager does not want to deny that the vehicles used sometimes leave deep tracks in the forest. "There's no other way, because we have to get in with heavy equipment." But the harvester is not allowed to drive criss-cross, regulations and markings ensure this. A distance of at least 20 metres must be left between the individual back roads. There are sprayed markings on the trees to ensure that this is adhered to: a white double line indicates the course of the so-called logging lane. An orange line means: cut down. There are also bright orange dots on trees in the Hardtberg forest. In summer, these were the sign of nests of the poisonous oak processionary moth. There are many orange spots.

The work in the Hardtberg forest will be completed in about four weeks. The paths will be prepared again, Ertelt assures us. By the summer, the gaps that have been cut may be overgrown and no longer visible. Whether the remaining pines will survive the next hundred years is something the forestry graduate is not overly hopeful about. "More dry summers... Everyone can draw their own conclusions." The foresters are focussing on a site-appropriate deciduous forest with oak and sweet chestnut. But the felling has created a perspective. "The old trees have to make way for the new growth to come to light." (Original text: Jutta Specht / Translation: Mareike Graepel)