If you are out visiting the GSWA’s Conservation Management Area you may see a rotting log that looks like it was dyed an unnatural shade of blue-green.
What you are observing is the after effect of a magnificent little cup fungus, Chlorociboria aeruginascens or the “green elfcup”. The green elfcup or green woodcup is a teeny-tiny cup fungus that likes to grow on bark-free wood and favors oaks in particular (1). The genus name Chlorociboria comes from the Latin chloro meaning “pale-green” and ciboria meaning “cups” while the species name aerug means “blue-green” and ascens “becoming”.
While the actual fruiting body is more uncommon, the blue-green stained wood it leaves behind can be found regularly along trails and amongst the leaves around the swamp. This stained wood was particularly sought after and used in Tunbridge ware, a style of woodworking using in-lay originating in Kent, England where mosaics were made of different colors of wood (1). If you’re feeling lucky, take a closer look at these stained pieces of debris and you might see the tiny elfcups wearing the green themselves!
Author: Adam Palmer, GSWA Education Associate
“Rogers Mushrooms | Mushroom Pictures & Mushroom Reference“. Archived from the original on 2008-10-12. Retrieved 2020-3-17.
