Artillery Fungus: Identification, Prevention, and Removal
What is Artillery Fungus?
Artillery fungus, also known as shotgun fungus or cannonball fungus, is a fungus that develops on rotting wood in moist environments. It is characterized by its unique method of spore dispersal: mature fruiting bodies burst open, forcefully ejecting sticky, black spores into the air. These spores can travel up to 20 feet away and adhere to any surface they land on, leaving unsightly black stains.
Causes and Conditions for Growth
Artillery fungus is commonly found in wood chip mulch, but it can also grow on decaying trees, other rotting wood, and animal dung. It requires sunlight and moisture to thrive, and it typically occurs in cool spring and fall weather, with temperatures between 50 and 70 degrees Fahrenheit.
Identifying Artillery Fungus
To confirm the presence of artillery fungus, inspect the black spots with a magnifying glass. The spores are globe-shaped, and when the outer dark brown coating is scratched open, a whitish, gummy-like center is revealed.
Prevention
The most effective way to prevent artillery fungus is to avoid using wood chip mulch, which is its primary breeding ground. Instead, opt for bark mulch or cedar mulch, which are resistant to the fungus. Redwood mulch and cypress mulch are not recommended due to sustainability concerns related to deforestation.
Another preventive measure is to keep mulch dry by stirring it up regularly, especially in small yards. Artillery fungus cannot grow in dry conditions.
Removal
If artillery fungus does appear, prompt removal is crucial to prevent permanent staining. Different removal methods are appropriate depending on the surface affected:
Non-porous surfaces (e.g., siding, windows, cars):
- Scraping followed by soap and hot water
- Bleach water (1 cup bleach per 1 gallon water)
- Power-washing (only on suitable surfaces)
Porous surfaces (e.g., wood siding):
- Scraping the top layer of spores (may not remove all stains)
Disposal
Dispose of contaminated mulch safely in the trash to prevent the spread of the fungus. Do not compost or dump it in your yard.
Additional Considerations
- Freezing winter weather can kill artillery fungus, but germinating spores may remain and become active when the weather warms again.
- Artillery fungus can damage car paint if not removed promptly.
- Painting over artillery fungus on wood may result in a pebbled appearance.
FAQ
Will artillery fungus die in winter?
Yes, freezing temperatures can kill artillery fungus, but germinating spores may survive and become active later.
Does artillery fungus ruin car paint?
Yes, artillery fungus can damage car paint if not removed promptly.
Can you paint over artillery fungus to get rid of it?
Yes, you can paint over artillery fungus, but it may cause a pebbled appearance on wood surfaces.