A discolored roof can reduce the curb appeal of your house. The discoloration usually appears as black or brown streaks and is often mistaken for dirt, fungus, moss or tree droppings. If you find such stains on your roof then you should definitely not ignore them. These stains on asphalt shingle roofs are due to algal feeding.  The most common species blameworthy for this phenomenon is blue-green algae known as Gloeocapsa… Continue Reading