Overview
- Late June reports show cities from Munich to Kassel and many Berlin districts have identified new nests and closed parks, sports fields and parts of bathing areas to keep people away from the caterpillars' toxic hairs.
- The caterpillars' microscopic Brennhärchen contain the toxin thaumetopoein and can cause skin, eye and respiratory irritation and, in rare cases, life‑threatening allergic reactions according to regional health authorities.
- Specialist teams and municipal crews are using wetting, vacuuming, mechanical removal, controlled burning and biological or chemical agents to remove nests but firms say demand is outstripping capacity with dozens of teams working long hours.
- Local tallies underline the scale of the outbreak: Kassel reported about 300 affected municipal oaks, Munich closed parts of the Lußsee area after 11 trees were confirmed, and Treptow‑Köpenick barred two sports sites through early July.
- Beyond immediate closures, authorities warn the hairs can remain hazardous in old nests for years, private landowners must hire professionals to remove infestations, and officials link the wider spread to this year's warm, dry weather which could prolong high demand for control.