What Homeowners Should Know About Artillery Fungus
Artillery fungus is one of the most frustrating exterior issues a homeowner can deal with — and one of the most misunderstood. Many homeowners across Saratoga County, including Ballston Spa, Saratoga Springs, Clifton Park, Malta, Wilton, Charlton, Burnt Hills, Round Lake, and Halfmoon, first notice it after their home has been professionally cleaned.
It looks like dirt or paint splatter, but it is not something a standard house wash can remove.
Understanding what it is (and what it isn’t) helps prevent confusion and unrealistic expectations.
What Is Artillery Fungus?
Artillery fungus is a type of fungus that grows in:
● Mulch beds
● Decaying wood
● Shaded, moist areas
It produces tiny black spores that are literally launched into the air — often sticking to nearby siding, trim, and vehicles.
Once attached, the spores harden and bond tightly to surfaces.
What Does Artillery Fungus Look Like?
Artillery fungus typically appears as:
● Small black or dark brown dots
● Rough, tar-like spots
● Clusters near mulch beds or ground level
It’s often mistaken for:
● Dirt
● Paint splatter
● Fly droppings
But unlike dirt, it doesn’t rinse away.
Why a House Wash Won’t Remove It
A professional house wash is designed to remove organic growth and surface buildup — not hardened spores bonded to siding.
Artillery fungus:
● Is not water-soluble
● Does not respond to standard cleaning solutions
● Cannot be safely removed with pressure
Even aggressive washing will not remove it completely.
What Would Remove Artillery Fungus?
The only way to remove artillery fungus is:
● Manual scraping or stiff brushing
● Treating each spot individually
Even then:
● Removal is often incomplete
● It’s extremely time-consuming
● It can damage siding or finishes
Why Removal Often Causes More Problems
Scraping or aggressive brushing can:
● Disturb oxidized siding
● Leave shiny or faded patches
● Make treated areas look different from the rest of the house
In many cases, the result looks worse than leaving the spots alone.
That’s why professional exterior cleaners generally do not attempt removal — especially on oxidized siding commonly found on older homes throughout Ballston Spa and Saratoga Springs.
Does Pressure Washing Help?
No — and it usually makes things worse.
Pressure washing:
● Won’t fully remove artillery fungus
● Can damage siding
● Can permanently alter the appearance of affected areas
Once oxidation or surface wear is disturbed, it can’t be undone.
Why Artillery Fungus Often Shows Up After Cleaning
This causes confusion for many homeowners.
Before washing, artillery fungus may be:
● Hidden by dirt or algae
● Less noticeable
Once the siding is cleaned, the contrast increases — making the spots stand out more. The fungus didn’t appear because of washing. It was simply revealed.
Can Artillery Fungus Be Prevented?
There’s no guaranteed prevention, but risk can be reduced by:
● Avoiding mulch directly against the house
● Using alternative ground cover near siding
● Maintaining distance between mulch beds and exterior walls
Even with precautions, some homes in shaded areas of Saratoga County are more prone due to environment and moisture.
Our Approach to Artillery Fungus
When artillery fungus is present, we:
● Point it out when possible
● Explain what it is and why it won’t come off
● Avoid damaging siding trying to remove it
We believe honesty and preservation are more important than forcing unrealistic results.
The Bottom Line
Artillery fungus is not dirt, and it’s not caused by poor cleaning. It cannot be removed safely through house washing, and aggressive attempts often cause permanent siding damage or uneven appearance. Understanding its limits helps protect your home and set realistic expectations before any exterior cleaning service.
If you ever have questions about spots on your siding, we’re always happy to explain what you’re seeing and why.
