Giant puffballs are one of fall's hardest mushrooms to overlook. Sometimes as large as a basketball or bigger, the smooth white fungi can suddenly appear in lawns, pastures, forest clearings and other grassy places across southern Wisconsin.

The Wisconsin Department of Natural Resources says giant puffballs, Calvatia gigantea, are most commonly found in Wisconsin from late August through September and often appear several days after a heavy rain. Fresh specimens can still turn up into early October, and Wisconsin mushroom hunters have documented October finds for decades.

They are not unique to Wisconsin. Giant puffballs occur across much of North America and in other temperate parts of the world, including Europe. In Wisconsin, they are a familiar enough wild edible that the Wisconsin Mycological Society includes the species among mushrooms that regularly occur in the state.

Finding one is often a matter of watching the right habitat. The DNR recommends looking in lawns, forest clearings and pastures. Other references describe them in open woods and grassy areas. Because fungi can fruit in the same general places again, a productive location is worth remembering for future autumns.