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Ever seen these black spots? They’re weird!

Agent Clean how to deal with artillery fungus and black spots

Artillery fungus creates black spots “shotgun” effect on siding

How to Deal with Artillery Fungus

Agent Clean Tips for Combating the Black Spots

If you’re someone who enjoys gardening, you’ve probably used mulch at some point in time. If you live in a humid climate, you might have seen black spots “shotgunning” the side of your house, your deck, or your car. The spots can be annoying, unsightly, and difficult to eradicate. Unfortunately, you most likely have a case of sphaerobolus stellatus, commonly known as artillery fungus.

What is it?

Artillery fungus is a mushroom-type fungus that is cream or orange-brown color and shaped like a small cup and contains a spore mass. The mushroom opens and “aims” at bright light sources (such as reflection off of light colored siding) and propels the spore mass toward the light, thus earning it the name “artillery” fungus. The spores can be shot as high as a second story of a building.

How to get rid of the black spots

The unfortunate reality is that unless you call an exterior cleaning company such as Agent Clean within two weeks of the spores landing on your siding, there is not much we can do. Even if we are called within that time, it is expensive, time consuming, and a liability for us to clean as removing the spots requires high pressure and heat, which can lead to damaged siding. Unfortunately, the longer the spots are on the siding, the harder it is to remove. Spores left on siding for long periods of time, even if successfully removed, can leave stains. The best way to deal with black spots from artillery fungus is preemptive measures.

If you have mulch near the siding of your home, be sure to turn it daily to help keep the growth of artillery fungus at a minimum. Certain fungicides can also be used at your discretion and according to the manufacturers instructions and warnings.

Black spots from Artillery Fungus can be a real problem. Check your mulch for these little troublemakers, and for everything else exterior cleaning, give Agent Clean a call.


Images from Sphaerobolus Stellatus

Reference: How to Remove Shotgun or Artillery Fungus

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  • 8 Mar, 2016
  • Nathan

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