Witches’ Butter (Tremella mesenterica) is a common jelly fungus known by its bright orange colour and gelatinous appearance. This fungus is most often found growing on smaller sticks of hardwood species. This fungus needs a moist environment to thrive. As a native species of the West Coast of British Columbia, it can grow for much of the year due to our high frequency of rain. It maintains a slimy coating when in moist conditions. It often dries out and loses some of its shape, but it is able to revive back to the more gelatinous state after exposure to wet conditions.


While this jelly appears to be living on the dead wood upon which it is found, it is actually a parasite of the mycelium of another fungal species (a crust fungus). The bright orange jelly takes the nutrients that the crust fungus is hard at work liberating from the dead wood and uses them for itself. Used by some cultures as a traditional medicine, this fungus produces a special compound which is being researched for potential uses in modern medicine, such as immunostimulation, anti-diabetic, and anti-inflammatory uses, among others.