Lately, friends of mine have been going off gallivanting, then return home with arms full of a giant white orb, lighter than air and larger than life*. This mystery orb is colloquially known as giant puffballs, or Calvatia gigantea (great name, right?).
Puffballs come in various shapes and sizes, but any puffball larger than a softball in diameter is considered to be giant (mushroom-appreciation.com). Mushrooms are already the oddballs of nature. But puffballs are weird, even for mushrooms. They do not have obvious gills, caps, or stems like a typical mushroom. Puffballs also never grow on wood, instead preferring meadows or lawns, which accentuates their ball-like appearance.
At this stage in the seasons, giant puffballs around Northfield are still maturing, and are not ready to release their spores. It is easy to tell, because their exterior is still smooth and white. When puffballs are ready to release spores, their exterior becomes brown and splotchy, eventually cracking. Cracking is what finally releases spores. Puffballs are also unique in this way, as most mushrooms bear spores in their gills. But puffballs like to be quirky and mysterious, keeping their spores hidden inside them, that is until they crack.
In fact, puffballs are only edible during their immature phase, when their skin is still smooth and white. Some foragers refer to puffballs as the “tofu of mushrooms,” which I can vouch for–chopped up into cubes, it is pretty darn tricky to tell the difference between raw puffball and raw tofu!
Amazingly, the largest giant puffball on record was 150 cm across! Now that’s a lot of puff! Typically, puffballs on the larger side grow to be about 50 cm across (minnesotaseasons.com). They are the only native Minnesotan mushroom species that exceeds a measly 10 cm!
Next time you happen to take a nice autumnal stroll, keep an eye out for these charming beasts of nature.
*Please note, foraging is not allowed in the Cowling Arboretum. Please make sure to check the legality of your future forays into foraging.