Earthballs

        Earthballs are often confused with puffballs, since they superficially resemble puffballs and occur in similar types of situations. However, earthballs have a much thicker and tougher rind-like outer wall and the spore mass on the inside is purplish-black, which is darker than the spore mass in puffballs. More importantly, earthballs form mycorrhizal associations with forest trees whereas puffballs are decomposers of organic matter in the soil. In spite of the fact that members of the two groups are similar in appearance, they are not closely related.