Bird's nest mushrooms grow crowded together on a forest floor in Dedham. Credit: Aislinn Sarnacki / BDN

The gravel road stretched before us as it did every morning, a straight shot down a steep hill. Beech trees lined the margins, their branches stretching out to offer some dappled shade during our daily walks. Here and there, a great white pine rose above the leafy canopy, it’s thick trunk as straight as a ship’s mast.

Beneath one of these mighty evergreens, something caught my eye. Masses of dark brown, like someone had poured chocolate all over the forest floor. I instantly veered off course to take a look, pulling my leashed dog, Juno, with me.

As we drew closer, the mysterious blobs of brown came into sharper focus with greater detail. Still, I needed to scooch down and nearly put my nose to it before I could see what it truly was: some of the oddest mushrooms I’d ever seen.

Bird’s nest mushrooms grow crowded together on a forest floor in Dedham. Credit: Aislinn Sarnacki / BDN

Tiny cups with grooved edges, the mushrooms looked like the paper cups that hold peanut butter cups or boxed truffles. Measuring less than a half- inch wide, the tiny fruiting bodies grew clustered together by the hundreds. And it gets weirder.

Inside each cup-shaped mushroom sat three or four dark seeds, or beans, or eggs. At the time, I wasn’t sure what they were. But something gnawed at the back of my mind. I’d seen something like it before — not in person, but in a photo.

So I returned home and looked up the first name that popped into my head: bird’s nest fungi. I’d seen it in one of my mushroom field guides in the past. And while many things I read don’t last very long in my brain, that particular name stuck with me. Perhaps it’s because it so accurately describes what I think is one of Maine’s oddest mushrooms.

A quick internet search told me that I might be correct in my identification, but mushrooms are tricky. So I posted the photos to Maine Mushrooms, a private Facebook group with more than 13,000 members. A few members stated that they, too, thought it was bird’s nest fungi. No one refuted my claim. So, as any cautious amateur naturalist will do, I did a little more research.

As it turns out, bird’s nest fungi are even cooler than they look. Their “eggs” are actually spore-containing structures called peridioles that are launched from the cup-shaped mushroom by raindrops. A drop will splash into the cup and throw the egg skyward so that it lands outside of the cup — sometimes even a few feet away.

Attached to each egg is a cord that uncoils and stretches as the egg flies into the air. The cord, which has a sticky end called a hapteron, will often wrap around a twig or branch, attaching the egg to a new substrate. Then, when the egg dries, it splits open, releasing fungal spores and spreading the species farther into the wilderness.

I don’t know if I would have believed all that if I hadn’t read it from multiple university websites. Who knew mushrooms were so active?

There are several species of bird’s nest fungi, and each looks slightly different. Leafing through the “National Audubon Society Field Guide to North American Mushrooms,”  I found a likely candidate for mine to be the species Cyanthus striatus, also known as splash cups. Popping up from July through August, splash cups are a type of bird’s nest fungus found on dead wood, bark, twigs and wood chips in open woods, which is exactly where I found them.

The written description continued to fit what I’d seen in the woods. The mushrooms’ cups flared out slightly at the top. Shaggy hairs covered their outer walls. The “eggs” were dark and, while rounded, slightly triangular in shape. And a white lid covered some of the cups.

The other two bird’s nest mushrooms in the book — common gel bird’s nest and white-egg bird’s nest — differed in texture and color from the type I had found.  

Speaking of mushrooms who shoot things into the air, the aptly named cannon fungus (also known as artillery fungus and the sphere thrower) is sometimes mixed up with bird’s nest fungi because it, too, throws spore-filled balls into the air. With the scientific name Sphaerobolus stellatus, the tiny, yellow-orange mushroom grows a slippery, spherical mass that is catapulted in reaction to light and moisture.

According to material provided online about cannon fungus by the University of Maine Cooperative Extension, its presence can be quite the nuisance, especially if it’s growing around cars, buildings or other objects that you’d prefer weren’t stained with little black dots. The mushroom can shoot the spore-filled mass a distance of up to 20 feet, and the sticky coating that causes it to adhere to surfaces will produce black spots that are difficult to remove.

Luckily, that’s not what I found near my house. I went back to double check.

Like other mushrooms, bird’s nest mushrooms change in appearance as they mature. Here you can see the mushroom’s fruiting bodies at various stages. Credit: Aislinn Sarnacki / BDN

It’s funny how many more details in nature stand out after you’ve done a little research. On my second visit to the bird’s nest fungi, I noticed several thin cords draped over the cups, with eggs dangling at one end. Searching for more launched eggs, I picked up a few wood chips and twigs near the site, and on each one, at least one egg was adhered with a cord.

It seems likely that bird’s nest fungi will continue to grow in that spot in the future, and they may even spread out to cover more of the forest floor.

I feel lucky to have such an interesting species growing close to home. I probably wouldn’t have noticed them if I hadn’t been on my daily walking route, where new features, such as a fallen tree or fresh woodpecker hole, pop out at me.

Finding the mushrooms reinforced an important lesson I’ve learned since becoming more interested in nature: Look closely. Pick a square foot of forest floor or lawn or riverbank, get down low and stare at it like a “Where’s Waldo” book. Use a magnifying glass, even. I’m confident that you’ll find all sorts of interesting things, like mushrooms that toss eggs into the sky.


Aislinn Sarnacki

Aislinn Sarnacki is a Maine outdoors writer and the author of three Maine hiking guidebooks including “Family Friendly Hikes in Maine.” Find her on Twitter and Facebook @1minhikegirl. You can also...