The future of spruces: bark beetle threat to great heights

The future of spruces: bark beetle threat to great heights

The future of spruce: challenges and solutions in German forests

threat from the bark beetle

In the German low mountain ranges, where the spruce was considered stable for a long time, a serious crisis spread: the book printer bark beetle has also reached highs over 650 meters. This development was clearly addressed by Henrik Hartmann, head of the Institute for Wald Protection at the Julius Kühn Institute in Quedlinburg. "Nothing is certain," said Hartmann. This invasive type, which usually increases in lower locations, now finds suitable conditions in higher regions due to climatic changes.

changes in the ecosystems

The rising temperatures and the associated dry periods not only have an impact on tree health, but also on the composition of the forests. Michael Rudolph, spokesman for the Lower Saxony State Forest, speaks of a dramatic decline in spruce stocks in the Harz. "From 2018 to 2022 we had a massive infestation, even in the highest mountain areas," explains Rudolph. The weaker tree structure, which is caused by drought, makes the spruces particularly attackable.

The situation in the Black Forest and Bavarian Forest

Markus Kautz from the forest and research institution Baden-Württemberg reports similar problems in the Black Forest, where the bark beetle no longer only becomes more active on the tree line, but also at high altitudes between 1000 and 1500 meters. In Bavaria, on the other hand, Tobias Frühbrodt speaks from a relocation of the infestation to up to 1000 meters. While the situation in the Bavarian Alps is still stable, other regions in Austria already show a mass increase in the beetle at 1600 meters.

mixed forests as a future model

The need to diversify the forests in Germany is becoming increasingly obvious. Experts like Johannes Schmitt from the German Forestry Council agree that the future of spruce is not in monoculture. "In a mixed population, the spruce has little chance of survival," explains Schmitt and outlines a new tree composition that could include species such as the white fir and the mountain hamper. The transformation to mixed forests is a lengthy task because trees need many decades to grow.

A call to preserve the forests

Despite the major challenges in front of which the spruce faces, we should not give up all hopes. According to Rudolph, every living tree is important: "We are grateful for every old tree that lasts for a few more years." In the time of the transformation of the forests, it is crucial to protect the existing tree population and to rely on a sustainable future that is resistant to the threats to climate change and pests. The forests, which may soon have to look different, are not only an ecological, but also a cultural heritage that needs to be preserved.

- Nag