Long periods of drought, numerous pests: The tree population in Germany is shrinking. This is shown by new satellite data. Regions where many spruce trees have been planted are particularly affected.

The tree population in Germany is shrinking. Between autumn 2017 and autumn 2024, more than 900,000 hectares of forest were lost, according to satellite data analyzed by the German Aerospace Center (DLR). This represents approximately 8.5 percent of Germany’s forest area. According to the DLR, losses have almost doubled since 2021.

The results show that the DLR estimates a greater forest loss in Germany than other findings. The Thünen Institute, which compiles the annual Forest Condition Report, estimated the area requiring reforestation after damage at around 490,000 hectares. Last year, the German Forest Owners’ Association estimated the figure at around 600,000 hectares.

The 900,000 hectares identified by the DLR also include areas that have either already been reforested or where trees were felled due to human intervention.

Harmful influences

The analyses yielded similar results regarding the most affected regions and the question of their causes.

“Environmental influences and pest infestations have left their mark on our forests,” says Anke Kaysser-Pyzalla, Chair of the DLR Executive Board. Unusually severe droughts, heat waves, and storms have taken their toll on Germany’s forests in recent years. The stressed trees are also vulnerable to pests, leading to tree deaths in many places, and in some cases, large-scale felling is necessary.

Central Germany is particularly affected

According to the German Research Center for Environmental Research (DLR), the Harz Mountains, South Westphalia, southeastern Thuringia, and the border region between Saxony and the Czech Republic are particularly badly affected.

This is also confirmed by a study conducted last year by the Helmholtz Institute for Environmental Research (UFZ). Regions such as the Harz Mountains, the Thuringian Forest, the Sauerland, and Saxon Switzerland have shown increased forest damage since 2019, according to the analysis.

The damage is particularly severe in the forests of the low mountain ranges where spruce trees were planted after 1945. However, significant losses of pine, beech, and oak trees were also recorded in some regions.

Experts: Droughts will increase

Extreme weather events such as unusually severe droughts and heat waves will continue to increase due to global change, according to the DLR. The spruce forests that dominate Germany, for example, have already suffered drastic losses due to the dry heat and the resulting increase in bark beetle populations – this trend is expected to continue in the coming years.

It is therefore crucial for forest management to anticipate such trends.Long-term satellite data time series make it possible to continuously monitor large forest areas and detect changes. “The data so far clearly shows that pure cultures of spruce, pine, and beech are particularly at risk,” the DLR stated.

Mixed forests, on the other hand, are more resilient and exhibit a better risk distribution. The key to healthy forests: biodiversity and a mixed forest structure with both young and old trees.

Read the original German publication.

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Soil under pressure – Germany’s soils are under pressure: they are burdened by drought and high nitrogen inputs, increasing compaction, and the loss of humus. The condition of Germany’s soils is regularly analysed at the Thünen Institute. Our current thematic focus highlights the findings, insights and recommendations for action. https://www.thuenen.de/en/thuenen-topics/soil/thematic-focus-soil