A mysterious, gelatinous substance nicknamed “Masło wiedźmy” (Witch’s Butter) is causing concern in forests across Poland. This unusual, jelly-like material has been appearing on trees and vegetation, prompting questions about its origin and potential impact on the ecosystem. Experts believe the substance is likely a form of fungal growth, specifically a plasmodial slime mold, but further research is needed to confirm this. While generally not harmful to trees, the appearance of “Masło wiedźmy” is unsettling to forest visitors and raises questions about environmental changes potentially contributing to its proliferation. Forest authorities in Poland are monitoring the situation and educating the public about the phenomenon. The substance is attracting attention due to its unusual appearance and the folklore surrounding similar occurrences.