Post by Brett Peto

Until recently, I haven’t given mushroom (much room) in my head to the Fungi kingdom. It’s been an admitted blindspot in my nature knowledge for too long. I’m taking some steps to correct this, though. Reading books such as Entangled Life by Merlin Sheldrake. Looking for fungi in the Lake County Forest Preserves in northern Illinois and other natural areas. Taking photos of the ones I find and doing my best to identify them.

There’s still much I don’t know—apologies for any errors in advance—but I can claim to know a bit more now than I did at the start of 2021. With fall being possibly the best time to spot some fungi, I thought I’d write about some common species you might discover in the preserves.

Some fungi facts might help set the table. Examples of fungi include yeasts, molds and mushrooms. They’re eukaryotes, meaning they have well-organized cells complete with a nucleus and organelles. Unlike plants, their cell walls contain a substance called chitin, also found in the exoskeletons of insects and crustaceans.

The building block of a fungus is the hypha (plural hyphae), a small tube that contains one or more cells. When hyphae connect and gather in great numbers, they form a network called a mycelium (plural mycelia). What we often notice above-ground this time of year are structures called fruiting bodies. As a method of reproduction, fruiting bodies release trillions of spores, which can each germinate into a new fungus and can be thought of as somewhat analogous to plant seeds.

Despite this, fungi are more closely related to animals than plants, though scientists lumped them in with the plant kingdom as recently as the 1960s. This in-between state—not quite animal, not quite plant, “supple, with a fleshy resistance”—leads many people to feel vaguely unsettled by fungi. It’s like only partly recognizing yourself in a mirror.

Do fungi photosynthesize as plants do? No, and they don’t actively track down prey and digest it internally as animals do, either. Rather, a fungus’ hyphae secrete chemicals called exoenzymes that break down organic matter surrounding them. The fungus then absorbs the nutrients that are released. Fungi are the only organisms on Earth which can effectively process lignin—an extremely tough component of plant cell walls.

These traits make fungi strong decomposers, releasing nutrients from dead organisms to free them up for themselves and other lifeforms. When a tree falls in a forest, it does make a sound, but it wouldn’t decay very fast without fungi around to dismantle it. Indeed, it’s hard to imagine plants and animals existing in their current forms today without fungi, since nutrients would be much harder to “unlock.”

The Fungi kingdom is so diverse that estimates of the number of species are diverse themselves, ranging from 500,000 to one trillion. A 2021 study published in the scientific journal Microbiology Spectrum pegs the number of Fungi species in the world somewhere between 2.2 and 3.8 million. However many fungi friends there are, scientists have discovered and described only about 120,000 species, perhaps just 3 to 8 percent of the total.

It’s moments like these when nature inspires both awe and humility. Flip through any field guide to mushrooms and you’ll see astonishing varieties of shapes, colors, sizes and textures. (I’m partial to puffballs, polypores and coral-like mushrooms myself.) Then consider that we literally don’t know the half of what’s out there. It makes a walk through the woods this time of year feel like a special expedition into partly charted wilderness.

So, here are 10 fungi species you may encounter locally. Many of these photos are supplied by my colleagues, Executive Assistant Helena Keller and Restoration Ecologist Ken Klick, both fungi aficionados themselves. There’s fungus among us, indeed!

One note of caution: fall is a wonderful time to spot fungi growing. But it’s never a good time to remove them from the preserves. Poaching and foraging are illegal. Those discovered doing so may be subject to fines according to the poached item(s). Let’s all do our part to keep these species in the preserves where they belong.