Witch’s butter

Tremella mesenterica

The witch’s butter is like a spoon of shiny, brilliant jelly growing on fallen evergreen oak woods. Its colorful yellow stands out on the black holm oak woods. It is parasitic over wood decaying crust fungus of genus Poniophora. Its taste and odour are unnoticeable. It’s quite common in Bages district. The witch’s butter is similar to Dacrymyces chrysospermus, though this species grows on coniferous woods, mainly from pine and fir trees. Dacrymyces chrysospermus is found in higher altitudes in Catalonia than district of Bages. The golden ear (Tremella aurantia) is even more similar. The golden ear is shaped in lobes, opal rather than clear, and it is parasitic over Stereum hirsutum.

The witch’s butter (Tremella mesenterica), like Juda’s ear (Auricularia auricula-judae), is a jelly fungus. Jelly fungi are the reproductive organs of orders Auriculariales, Dacrymycetales and Tremellales from Basidiomycota group. Most of mushrooms belong to Basidiomycota phylum of fungi. Basidiomycota have basidiocarps, these are reproductive structures with bottle or caw udder shape that produce 4 spores. The basidiocarps from Tremellales and Auriculariales, as well as that from some parasitic fungi, have internal divisions, while the ones from remaining Basidiomycota orders do not. The internal divisions of Tremellales basidiocarps display a cross, while Auriculariales ones display three transversal walls. The witch’s butter and the Juda’s ear both may dry, lose original shape and become fragile (photo 2). However, they’ll recover as soon as hydrated again.

[photos Jordi Badia]