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What Is Artillery Fungus?

Have you ever noticed tiny black dots on the bottom of your siding and wondered what they were? If so, your home might be affected by artillery fungus. Read on to learn exactly what artillery fungus is, how to get rid of it, and how you can help to prevent this mulch fungus from reappearing.

Artillery Fungus and its Many Names The dark spots you see on your siding is a wood-decaying fungus commonly referred to as artillery fungus. You can find it in dead trees, rotting wood, and mulch. It goes by many names, also being referred to as shotgun fungus, artillery mold, or its scientific name, Sphaerobolus stellatus. It is usually found in non-composted mulch because non-composted mulch doesn’t go through a burning process that would normally neutralize the fungus. Connected to the fruiting bodies are spore masses that are dark brown at their tips. The spore masses in nature launch out of the fruiting bodies toward the sun. Around your home, however, the fungus perceives your bright-colored siding as sunlight. The spores subsequently shoot out toward the bottom of the house, mistaking your biggest investment as a good place to reproduce. The tiny black dots resemble a shotgun spread pattern, hence the colloquialism, “artillery fungus”. Once it lands on the siding of a home and sits, it goes into a dormant phase. The sticky, almost super-glue-like spores become nearly impossible to completely remove if left on a home for too long. How to Get Rid of Artillery Fungus The removal process puts the siding of a home at risk for significant damage and possibly even replacement. Power washing is not the answer here. While the presence of artillery fungus is usually a sign that a home needs power washed for other reasons such as algae and mold prevention, treating a home specifically for artillery fungus requires the use of a steel cloth or another abrasive tool. Beware of any pressure washing company or cleanser that claims to be able to remove artillery mold without an abrasive tool. The amount of water pressure required to remove artillery fungus would in most instances void the warranty on your siding, and if any water is pushed up underneath the panels, mold could grow.

You should be extremely cautious when using an abrasive solution on the siding to your home. It is always best to start light and work your way up to stronger solutions to minimize the risk of damage. After removal, artillery mold could leave behind a brown residue that will become embedded in the siding if left for too long. The good news is that artillery mold is purely cosmetic. It poses no health threat to homeowners, pets, or wildlife, as it belongs to the same class of fungi as the mushrooms we eat. Suggestions to Prevent Artillery Fungus The best way to prevent artillery mold is to keep it away from your home in the first place. Avoid purchasing dark-colored, non-organic, and non-composted mulch. If you have dark-colored mulch, consider switching to a light-colored composted mulch that has gone through a baking process to neutralize the fungus. You additionally will want to walk around your home every six months to ensure that your siding is free from not only artillery fungus but also dirt, algae, mold, and mildew. We recommend scheduling a power wash every spring to prevent a buildup of contaminants that can eventually damage your siding.


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