Behold the Mighty Bird’s-Nest Fungi

My Peterson’s field guide to mushrooms indicates that these must be “splash-cup bird’s nests,” Cyathus stercoreus: the inside of the cups are smooth; the spore cases (peridioles) are dark and flattish; they’re growing on landscaping mulch, the cups are covered with a whitish membrane prior to opening, and immature cups can be kind of yellowish.

We found these critters growing in my parents’ front flower bed, opening their cheery little nesty-cups alongside the (somewhat shinier) petuneys.

Calling this type of fungus “bird’s nest” is fitting for more than just the cuteness factor (they look like little bird nests, don’t they!)—those round balls in the cups actually are, basically, the fungus’s “eggs,” the new generation, the precious offspring, hope for the future.

In the case of bird’s-nest fungi, raindrops disperse the spores when they hit into the cups, dislodging the round cases, which are somewhat sticky, which then adhere to nearby objects, such as plants.

The spore cases for at least one type of bird’s-nest fungus actually fly out of the cup, dramatically, as if they’ve been shot out of a cannon. You might have seen the aftermath of this when the little bitty sticky globs get adhered to the siding of your house, or on your car, leaving their empty nests behind.

Elio Schaechter, in his inspiring book In the Company of Mushrooms: A Biologist’s Tale (a book I could not live without), explains how the bird’s-nest fungus “gameplan” is a clever way to achieve dispersal. When a peridiole splashes or flies out of its cup and sticks to a nearby plant, there’s a decent chance that plant might be consumed by an herbivore.

Then, as with many “seeds” that get consumed by herbivores, the spores pass out of the animal’s gut in good shape. And it turns out that many of the bird’s-nest fungi feed on doo-doo, so there you go: dispersal, and then the first dinner, compliments of the chauffeur.

Miraculous, aren’t they? . . . What a wonderful world.