Mold is a type of fungi of which there are over 100,000 species. Mold digests organic matter and reproduces releasing spores into the air. Mold has 5 growth requirements; something to feed on paper (drywall), wood, natural fibers or some type of soil; moisture or humidity in the air; moderate temperature especially between 68 and 86 degrees; stagnant air with no movement; and time. Typically you can see visible growth within 72hrs. Read more.