Oaks affected by two diseases at the same time

Exposed damage on a Hungarian oak ( Quercus frainetto ) affected by both P. cinnamomi and acute oak dieback (Image: Ludwig Beenken, WSL) Five years ago, the bacterial complex disease acute oak dieback was also discovered in Switzerland. In 2023, a new root disease was also discovered on oaks, as reported by Forest Protection Switzerland in the new Forest Protection News . It is particularly worrying when both diseases affect oaks at the same time . Oaks are considered to be trees of the future because, compared to other common deciduous tree species, they suffer less from the consequences of climate change such as heat or drought. For some years now, however, the oak has been affected by a disease called acute oak dieback, which is caused by various types of bacteria. Extreme events such as long periods of drought may favor the disease. The bacterial species involved are indigenous.