Q: We have these small, black spots that look like specks of tar, all over our white, vinyl siding of our house. It’s on the porch, my windows, but it is worse on the siding. It goes all the way up to my second-story windows, and is even under my soffitt and on my gutters. What do you think it is? A: Sound like you have the infamous “artillery fungus”.
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 fruiting body of this fungus orients itself toward bright surfaces, such as lightcolored houses or parked automobiles. The artillery fungus “shoots” its black, sticky spore mass, which can be windblown as high as the second story of a house.