Artillery Fungus

There are black spots on white columns (sides) of the house.

Symptom(s):

Black spots appear on the side of buildings or other objects such as cars.

Cause(s):

The spots may actually be spores from members of a group of fungi commonly called the "shotgun" or "artillery" fungi in the genus Sphaerobolus. These fungi colonize dung or other organic matter such as wood mulch, wood benches, wood sheds, etc.  The spores may be propelled as far as six meters and adhere to surfaces.  They do not cause structural damage, but are almost impossible to remove.

Control(s):

No fungicide treatment is recommended at this time.  Changing mulch from wood to bark may lessen fungal spread.

Reference(s):