Yellow slime in the forest: What you need to know about witch's butter
Walking through the forest, we can encounter many unexpected phenomena. One of them is a mysterious yellow slime that can cause concern or even fear. Although its appearance resembles expanding foam, it is worth knowing what it is and what consequences it may carry if you come across it.
3 September 2024 15:09
During a walk in the forest, our attention may be drawn to yellow slime that looks like expanding foam. Witch's butter is neither a mushroom nor a plant. So, what is this mysterious secretion?
What is witch's butter?
Witch's butter (Fuligo septica) is a slime mould that occurs on all continents. Its name comes from its characteristic bright colour, which resembles melted butter. Depending on weather conditions, witch's butter can take various forms and colours—from bright yellow to brown. It most commonly grows on rotting tree stumps and leaves but can also be found on the ground.
This slime mould is very flexible and quickly changes position, giving the impression that it "moves" through the forest. Its unique ability to adapt and survive means it is found almost everywhere. Its presence is usually not dangerous to humans but can harm animals.
Is witch's butter dangerous?
Although witch's butter is not poisonous to humans, it can cause allergic reactions when it comes into contact with the skin. Contact with this slime mould can be dangerous for pets, especially dogs. A dog that licks or eats a piece of witch's butter may experience nausea, vomiting, and diarrhea. Therefore, pet owners should take special care when walking in the forest and avoid areas where this slime mould grows.
There have also been cases where witch's butter grew on a lawn in a garden or a city park. Therefore, attention should also be paid to avoiding contact with this slime mould in such places. Remember that even a casual walk can end with an unplanned visit to the veterinarian if we do not take proper care.
