These produce the spores. Young puffballs are uniformly white with a firm inside and a thin and fragile outer skin. As a puffball matures, all or a large portion of the white interior becomes yellow, then darker until it eventually becomes a dry, powdery, dark green to purple to brown spore mass. The thin outer skin may remain intact except for a hole at the top, or it may break away in large, irregular pieces. There are many kinds of puffballs, ranging in size from less than an inch to more than a foot, and weighing several pounds.
Most puffballs become noticeable in late summer and fall.
Since mushroom and puffball fungi grow on decaying organic matter, they are most likely to form on tree stumps, tree roots, or in other spots in the lawn with high organic debris. Although they will eventually disappear naturally after the organic food base is exhausted, this can take up to 10 years or more for a large stump or root. It is difficult to totally eradicate nuisance mushrooms and puffballs. Adequate control usually can be accomplished by digging up and destroying rotting stumps, roots, or other underground sources of organic debris. Mushroom problems can be prevented on new home sites by removing all discarded construction lumber from the site before sodding or seeding.