This algae growth usually begins as small spots and then eventually becomes visible streaks.
What causes black streaks on roof shingles.
Algae arrive on the rooftop through the air in the form of spores or clumps of cells.
While the streaks do not cause a great deal of damage they can cause the shingle to age prematurely.
Black streaks on shingled roofs are a common though mysterious sight.
The black streaks running down roofs are actually a hardy algae called gloeocapsa magma.
Here s what they are and what to do about them.
The most common type is known as gloeocapsa magma also known as blue green algae.
Most black streaks form on the northern slopes of roofs where it s darker and wetter ideal for algae growth.
Over time this algae accumulates developing a black outer coating which causes stains on roof shingles.
The streaks are caused by a type of algae known as gloeocapsa magma.
While not immediately damaging they can prematurely age shingles.
Black streaking on roofs is a common problem.
Although these dark spots and ugly black streaks on your roof may look like dirt mildew soot or mold what they really are is algae.
Algae may be mistaken for soot dirt or tree droppings most of which typically produce only localized discoloration.
As the blue green algae.
Algae growth on asphalt shingles.
They re actually algae otherwise known as gloeoapsa magma and they are as nasty as they are resilient.
Why are there dark streaks on my roof.