Black Substance On House Siding

The black stains on the vinyl siding shown at left may be a fungus or a black agae.

Black substance on house siding.

They are the reproductive structures produced by artillery fungus sphaerobolus stellatus one of several fungi common on wood mulches used around plantings in home and commercial landscapes. The black tar like spots that are all over your vinyl siding are more than likely a fungus called sphaerobolus stellatus better known as artillery or shotgun fungus. By the growth pattern we think this is almost certainly a dark colored algae. Are those spots alive.

Use these simple landscaping tips to prevent this from happening. In the absence of direct sunlight it shoots the spores at highly reflective surfaces such as white house siding. And of course the black spots show up better on white surfaces so they are noticed more easily. Watch as lou manfredini ace s home expert shows you an easy and affordable way.

If you re seeing dark specks on your siding the culprit could be hiding in your mulch. A microscopy lab examination of a sample from this surface would be needed to know for sure. In nature the artillery fungus shoots its spores towards sunlight. Although it s most often found on the east coast it can grow anywhere and especially thrives in areas that have cool damp springs or rainy fall weather conditions.

The dark spots are indeed spores but they do not come from your oak trees.