Q: So, what exactly is the artillery fungus?
A: The artillery fungus is a white-rotting, wood-decay fungus that likes to live on moist landscape mulch. It is in the genus Sphaerobolus (Greek for “sphere thrower”) and is very common across the USA, especially in the East, as well as many other parts of the world. The most common species in Pennsylvania seems to be S. iowensis (contrary to previous reports – including our own). The artillery fungus is technically a “Basidiomycete” fungus (like the common mushroom that we eat), and probably is most closely related to a group of fungi called “earth stars”. However, the artillery fungus is much smaller that the earth star that you may see occasionally growing in your yard. There may be other fungi and fungi-like organisms growing in your mulch.