Berlin: Despite the summer weather, the linden trees are suffering from wilted leaves

Berlin: Despite the summer weather, the linden trees are suffering from wilted leaves

Although summer is still in full swing, many lime trees in Berlin already have brown leaves. This sad sight is due to the prolonged dryness and warmth in spring, which have allowed the lime tree spider mites to multiply in large populations. When asked by the dpa news agency, urban nature expert Derk Ehlert from the Senate Environment Administration explained that the infestation was occurring more frequently this year than in previous years.

However, this condition is not a cause for concern as the trees can and will recover from it. Of the approximately 150,000 lime trees on Berlin's streets, not all of them are affected equally. The winter linden tree in particular is more severely affected by spider mites than the summer, Crimean and silver linden trees.

Another reason for the weakened lime trees is the drought of recent years. As a result, the trees are overall weakened and more susceptible to pests. Close observation is required to distinguish mite infestations from dry damage. In the case of drought damage, brown leaf edges can usually be seen, while mites cause yellowish to brownish discoloration of the entire leaf. Since the mites migrate from bottom to top, the lower parts of the tree are typically affected first.

The mites feed on the sugar-rich plant sap in the leaves. Due to the infestation, the trees can no longer carry out photosynthesis this season. The brown leaves fall off prematurely and there is a possibility of new growth.

This phenomenon occurs mainly in urban areas and less in forests. In general, it can be said that the more central the tree is in the city and the more sealed areas there are around it, the more likely it is to be affected by mite infestation. Trees that are already stressed and may also have salts in the soil are more likely to be attacked by the mites.

The Berlin government has already taken measures to counteract climate change and limit its effects on the city. This includes, among other things, greening roofs and increasing the planting of trees. These measures are intended to help cities and municipalities be better prepared for the consequences of climate change.

Overall, the brown leaf infestation on the linden trees in Berlin can be attributed to the combination of prolonged dryness, warmth and the increased occurrence of linden spider mites. However, the trees can recover from this, so there is no cause for concern. Growing new leaves and caring for trees are important steps in restoring their health.