The Culprit Is Usually Hardwood Mulch.
It forcefully ejects its mature spores high up in the air, leaving pesky stains.
What Is Artillery Fungus?
Sphaerobolus stellatus, commonly known as the shotgun fungus or cannonball fungushekakoskinen / Getty Images
They can land up to 20 feet away, preferably on light-colored surfaces.
The spores have a sticky coating which makes them adhere to anything they land on.
If you are unsure if its artillery fungus, inspect the spots with a magnifying glass.
Artillery fungus fruiting bodies after they burst and release the mature sporesweinkoetz / Getty Images
What Causes Artillery Fungus?
It needs sunlight and moisture to grow.
The fruiting bodies wont develop in weather above 78 degrees.
Simon McGill / Getty Images
Removing the black spots within two to three weeks after they appear is key for effective removal.
The longer the stains remain on a surface, the more difficult it will be to clean the surface.
Which removal method works best depends on the surface.
Scraping followed by soap and hot water is the gentlest option.
Power-washing, the strongest option, should only be applied on suitable surfaces.
How to Prevent Artillery Fungus
Artillery fungus develops mostly in wood chip mulch.
Choosing a different mulch is the best way to prevent it in the first place.
Use bark mulch or cedar mulch instead, as they are resistant to artillery fungus.
Redwood mulch andcypress mulchare not recommended for sustainability reasons as native forests have been depleted by timbering.
Artillery fungus wont grow in a dry environment.
If you have a small yard, stirring up the mulch regularly to keep it dry is another option.
Yet another alternative is to use anon-organic materialto cover unplanted areas, such as stone or gravel.
Freezing winter weather can cause artillery fungus to die.
However, the germinating spores could still be there when the weather warms again.
Yes, artillery fungus can ruin car paint.
The sticky spores can stick to the vehicle and it can be difficult to remove them.
you could paint over artillery fungus.
However, note that if you paint over artillery fungus on wood, it could cause a pebbled appearance.
