Some black stains on asphalt roof shingles are caused by a black algae sometimes misnamed as a black fungus or even a mildew such as that shown in the photograph here.
Fungus roof shingles.
Scrubbing or power washing the lichen will only do more damage.
Black algae stains may be mistaken for but are not extractive bleeding a product cosmetic defect.
The first one we will talk about is algae.
Lichen is a photosynthetic fungus that has roots that wrap around the granules feeding on the nutrients of the gm and the filler in the shingles.
Once on the roof lichen cannot easily be removed.
Some black stains on asphalt roof shingles are caused by a black algae sometimes misnamed as a black fungus or even a mildew such as that shown in the photograph here.
There are four common types of roof fungus that cause the most problems whether it be damage to your home or your health.
Even if it dries out it can come back to life when rain or moisture appears.
Algae will devour your shingles and is also attracted to moisture.