Germany battles oak processionary moth outbreak with health warnings and control measures

City officials in Koblenz reported that oak processionary moth infestation remained low in 2026, affecting about 13 % of registered oaks and 208 trees whose nests were removed promptly. In contrast, the Nuremberg Reichswald forest experienced a sharp rise in moth numbers, prompting the forest authority to warn walkers of health risks from the larvae’s urticating hairs, which can cause skin rashes, eye irritation and respiratory problems. Across Germany, health agencies have highlighted the potential for allergic reactions and advised the public to avoid contact with nests and to wash clothing thoroughly after forest visits. Authorities are employing biological control methods, including the use of nematodes and bacteria‑based insecticides applied by helicopter in regions such as Mecklenburg‑Vorpommern, Saxony‑Anhalt and Brandenburg, and have begun spraying near schools, cemeteries and sports fields. The rise in moth populations is linked to warmer, drier conditions associated with climate change, though the overall risk to oak vitality is considered limited at present.