Artillery Fungus……. Is that FLY POOP on my siding!

Its not fly poop. Its Artillery fungus on siding cleaning

I can’t recall how many times I’ve had the “Fly Poop” discussion. It is artillery fungus in most occasions.

Are those little black specks on your siding Fly Poop?  Sometimes, sure, but if the specks look like what is pictured here, the answer is NO, it’s not fly poop.  I’d like to review with you what the black specks are, why you have them, and what you can do to prevent them.

The small black spots as pictured, are actually Artillery Fungus.  They typically grow in almost perfect cirlces. If you take your fingernail to them a top layer will come off, but under that is still tiny roots are present. Another name some use is “shotgun spores.”  The reason they are named artillery or shotgun is because of the way they spread themselves.

Artillery fungus is present in your mulch.  Homeowners that do not use mulch very rarely have any problems with Artillery Fungus.  If they do, it just may be from their neighbors mulch.  How can that be?  It is from the way these spores spread themselves.  When the environment is right the fungus will pop or shoot up into the air.  Anything that they land on or the air carries them to they will them attach themselves to.  This includes siding, painted surfaces, even your cars.


Unfortunately, there is no easy way to remove the spores once they attach.  However, if you notice them right away, chances are MUCH better of removing them if we get right too it.  Once their roots grow into the surface they are darn near impossible to remove.  They do have a life cycle which runs 7 to 10 years.  After their life cycle they are said to come off much easier.

If new, call Power Play Inc. right away if you are in the Lancaster, Lebanon, or surrounding counties.  They will be removed with Hot water applications and pressure washing.  If the spores have been on your siding for longer then a month or so, then the stubbornness of the fungus will be evident.  Some power washing companies claim to be able to remove them but I can tell you from personal experience that they are either baiting you in, or they plan on blasting your siding with extreme pressure and heat which can warp and damage your property.  This really isn’t recommended and all of the spores will definitely not be removed.

Pro Active vs. Re Active

Well you can wait out the life cycle of the spore or try Magic Erasers.  Mr. Clean magic erasers is the only manner of removing them that I have found to work at all.  That’s right the cleaning erasers found in your cleaning aisle.  This is a ton of hard work but if they really bother you, this is a safe way to try and remove some of the spores.

Be proactive, there are several things you can do to minimize or completely eliminate any artillery fungus problems.

So here it is…… Power Play Inc.’s recommendations to avoid Artillery Fungus problems.

  • Don’t use Mulch (especially mulch that comes from dead trees and limbs that have been rotting – cedar mulch is known for not carrying the fungus)
  • Use decorative stones instead of mulch (less maintenance each year for sure)
  • Try the NEW rubber mulch, I personally use this with great success!
  • Talk with your mulch supplier or landscaper (let them know that you are informed and do not want mulch that may contain or harbor artillery fungus)
  • Mix Mushroom Compost with your mulch (it is believed that if you mix about 40% mushroom compost with your mulch the artillery fungus can not survive)

So that’s it, the lowdown on the black spots or specks, if you have any other questions at all feel free to contact Power Play Inc.

Also, Penn State, has some good information as well.  Check out their article, HERE.

Just because the fungus is not easily removed, does not mean we can not improve the surface greatly with a safe solution based cleaning. Please fill out our contact form so that we can discuss your specific needs. CLICK HERE

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