Witches’ butter, this fungus lives on dead branches of deciduous trees, either still on the tree or on the ground.
Do not confuse with:
Brown witch’s butter (Tremella foliacea) – also known as Leafy brain – sometimes becomes almost black and also occurs on softwood, unlike Witches’ butter.
Witches’ butter (Exidia nigricans), is a jelly fungus in the family Auriculariaceae. The fungus lives off the decay of dead wood. Witches’ butter occur on dead branches of deciduous trees, both still hanging from the tree or lying on the ground. More likely to be found on thick rather than thin branches. Witches’ butter causes white rot in dead wood.
This fungus is found in Europe and North America.
The fungi grow in groups and are rubbery to the touch. Over time, the fungi coalesce into a large shiny, black, pleated centimeter-thick layer. During dry periods, the layer shrinks to a thin brittle black crust to swell again in wetter seasons.
Witches’ butter is not poisonous, but neither is it edible.
