Overview
- Mid-July reporting shows active, widespread infestations in multiple states with Thuringia now recording detections in nearly all forest offices.
- Bremen has logged more than 5,800 cases this season and Kassel’s Hessen Kassel Heritage says roughly 3,000 oaks in the Karlsaue are believed infested.
- Only the caterpillar stage is harmful because its microscopic hairs contain the protein thaumetopoein, which can cause skin rashes, eye inflammation and breathing problems; local hospitals have treated a small number of possible related cases.
- Authorities are prioritizing professional removal at high‑use public sites such as parks, playgrounds and school grounds while leaving forest nests for closures and signage, but crews face shortages of trained staff and protective gear and cities face six‑figure costs.
- Larval activity should decline when caterpillars pupate in late July into August, but officials warn hairs can persist in old nests and climate trends of milder winters and drier summers raise the risk of recurring mass outbreaks.