The myriad of mushrooms that dot our landscape, from suburban front yards to local forest preserves, often seem to blend together. The sameness of colors in many local species, from light brown to dark, and from white to off-white, can confuse the mycological newcomer. But at least one fungus common to Chicago Wilderness clearly sets itself apart. Laetiporus sulphureus, also known as the sulphur shelf or chicken-of-the-woods, declares its presence with a bright orange top and gorgeous sulphur yellow underside.

"The neat thing about Laetiporus is that it's impossible to misidentify," says Greg Mueller, curator of mycology and chairman of the Field Museum's botany department. "It's the only big, bright orange bracket mushroom with sulphur pores growing on wood out there."

Called a bracket or shelf mushroom because of the way it extends from tree trunks, the sulphur shelf is nearly always found on or around oak trees in our nearby forest preserves. While looking for sulphureus, mushroom hunters may also spot its less brilliantly colored cousin, Laetiporus cincinnatus, which grows from roots on the ground and is pinkish-orange on top and white underneath.

These two species are most accurately called polypores because, rather than sporting gills underneath their caps like true mushrooms, they have tubes, or pores. The mouths of the tubes appear as tiny holes dotting the mushrooms' undersides. The tubes don't develop immediately, however, and only a close look will reveal that the bottoms of these shelf mushrooms aren't actually solid.

The sulphur shelf usually gathers in giant clusters, says Leon Shernoff, president of the Illinois Mycological Association and publisher of Mushroom: The Journal of Wild Mushrooming. Easiest to find in summer and early fall, the fungus may grow inside a tree for some 50 years in order to build up enough energy to form the bright fruiting bodies that sprout from the tree's exterior. During that time, the fungus is decaying the heartwood (the wood at the center of the tree's trunk), creating hollows for creatures to nest in. The work of these shelf mushrooms also speeds the transformation of the tree into soil.

Laetiporus sulphureus is an important fungus at the base of the forest food chain, explains Shernoff. Inside the tree, springtails, nematodes, and other tiny beings graze on the fungus. Outside the tree, fungus gnats, fungus flies, pillbugs, and various fungus beetles munch on the shelf. Birds, in turn, pick these off for a meal.

Humans can participate directly in this food chain as well. Mushroom aficionados say the texture of the sulphur shelf resembles chicken. Those with an interest in eating it, however, should be aware that, as with any mushroom, some people have a bad reaction, including light-headedness and nausea. Mueller suggests eating a few tablespoons at first to make sure you won't become ill. Avoid eating old, shriveled, and moldy sulphur shelf, or those growing from conifer or eucalyptus trees, and always cook before eating. (Another warning: In many forest preserves and state parks, there are restrictions on collecting mushrooms.) Collect only the young outer inch of the fruit, which will regrow and has the tenderest texture. Mueller likes to batter his L. sulphureus in beer and cracker crumbs, then sauté it in oil. Shernoff likes to singe his in a frying pan over high heat for a smoked chicken effect.

The sulphur shelf is abundant and hasn't been tremendously affected by pollution or other human encroachment. So the next time you take a walk through the woods, let your eyes wander, and eventually they may catch sight of this bright orange-and-yellow standout.

For more information on wild mushrooming, visit Mushroom the Journal.

—Anne E. Stein