The witch's butter (Tremella mesenterica) is a jelly fungus, like a spoon of orange marmalade growing on fallen evergreen oak woods. Its shiny, brilliant colour stands out on the black holm oak woods. It's quite frequent in Bages. The jelly fungi like witch's butter are a small group of basidiomiceti, the phragmobasidiomiceti, that separate from the well known homobasidiomiceti that produce the typical mushrooms. [photo Jordi Badia]