Tiny Turquoise Mushrooms!
Identified for the CFC by instagram photographer @fungiwoman, Chlorociboria aeruginascens, a/k/a green elfcup, is the fungus behind that gorgeous turquoise wood you’ll find on Pennsylvania trails.
While the stained wood is common, spotting the tiny, 2-5 mm diameter fruitbodies is a rarity. They occur in summer and fall in the Northeast – these were found on 2 Sept 2020, on Cook Trail in Cook Forest State Park, Pennsylvania. Green elfcup prefers hardwoods, particularly oak, and little shards of the fallen wood that has hosted it can be found on trails and amongst the fairy moss, which seems fitting.
Etymology: aeruginascens is Latin meaning “becoming blue-green”
“Fourteenth and 15th century Renaissance Italian craftsmen used the wood to provide the green colors in their intricate inlaid intarsia designs” – to see some examples, and read some heavy-duty science, visit this link to a botany page of the University of Wisconsin-Madison.