Minnesota Fungi

Morel mushrooms (Morchella spp.) are some of the best known and most sought after wild mushrooms in North America. They are particularly abundant in the upper Midwest. They are edible, considered delicious, and are hunted for in deciduous woodlands every spring. False morels (Gyromitra spp.) look superficially similar and appear at the same time of year in roughly the same areas. However, false morels are poisonous. They contain the chemical gyromitrin, which is metabolized in the body into a volatile chemical used as a rocket propellant.

Gabled False Morel (Gyromitra brunnea) is the most common false morel in Minnesota and Wisconsin. It is found in the spring, alone or in groups, on the ground under hardwood trees. The cap is tan to reddish-brown, 2″ to 4″ wide, and loosely wrinkled. It is usually saddle-shaped or winged, divided into 2 or 3 strongly projecting lobes that are fused to each other.

Snow Morel (Gyromitra gigas) is a common early mushroom in forests of North America. It is called a “false morel” due to its similarity in appearance and seasonality to true morels. It is found in the spring and early summer alone, scattered, or in groups, on the ground or on rotten wood, under coniferous or hardwood trees, often poking through leaf litter. It is saprobic, obtaining nutrients from rotting wood, and might also be mycorrhizal, having a mutually beneficial relationship with the tiny rootlets of trees. It may exhibit both traits at different parts of its life cycle.

Snow Morel is edible if sautéed but not edible when raw. Some authors suggest that it be avoided due to its similarity in appearance to the poisonous False Morel (Gyromitra esculenta).

Snow Morel is identified by the squarish, blocky, convoluted cap that is compact and rarely has projecting lobes; and the massive, ribbed or longitudinally wrinkled stem that is often mostly or completely hidden by the closely appressed cap.

American Eastern Yellow Fly Agaric (Amanita muscaria var. guessowii) is a large, conspicuous, yellow variety of one of the most recognizable mushrooms in the world. It is widespread in North America, common in northeastern United States, and not uncommon in Minnesota. It occurs in coniferous, deciduous, or mixed woodlands, woodland edges, and among planted trees. It is found from June to November, solitary, scattered, in groups, or in fairy rings, on the ground under pine, spruce, fir, aspen, or birch trees. It is mycorrhizal, obtaining its nutrients from the rootlets of a tree while facilitating greater absorption of nutrients from the soil by the tree.

Most guidebooks and authorities state that American Eastern Yellow Fly Agaric is poisonous, and it is true that about 90% of mushroom-related fatalities involve Amanitas. Fly agaric contains the hallucinogenic compounds muscimole and ibotenic acid. They may have been involved in prehistoric rituals. It is poisonous in large, possibly even in moderate amounts, but not normally fatal.

Mushrooms in the genus Amanita are identified by pale gills usually not attached to the stem; a white spore print; a universal veil that creates a sac-like base or other distinctive feature at the base of the stem; and caps that are more or less dry. Fly Agarics (Amanita muscaria) are identified by cottony scales on the cap; a partial veil that creates a persistent ring or collar of tissue at the middle or near the top of the stalk; and one ring or two to four concentric rings of scales at the base of the stalk. American Eastern Yellow Fly Agaric is distinguished by a bright yellow or orangish-yellow cap that is often reddish-orange or yellowish-orange in the center.

Split Gill (Schizophyllum commune) is one of the most common and widespread mushrooms on the planet. It occurs on six continents, absent only from Antarctica, where there are no trees to support it. It is also one of the best studied fungi species. The genome was sequenced in in 2010, and it is often used in the laboratory because it fruits so readily.

Once thought to be a single species with worldwide distribution, Split Gill is now known to be a complex of several closely related species that cannot be reliably distinguished based on their morphology. There are more than 28,000 sexes of Schizophyllum commune. Each individual is sexually compatible with 27,997 (99.98%) of other individuals worldwide.

Split Gill is found year round, scattered, in small groups, in rows, or in fused clusters, on stumps, logs, and sticks of dead hardwood, especially oak. Worldwide it is found decomposing more than 150 different species. The cap is whitish or grayish, densely hairy, and small, less than 1½″ in diameter. The “gills” appear hairy when dry, smooth and split down the middle longitudinally when moist. They close up in dry weather, protecting the spores, and open when moistened. Split Gill is considered inedible in North America and Europe due to its toughness and small size. However, it is used in the cuisines of places with dryer climates, where fleshy mushrooms are difficult to transport to market.

Ravenel’s Stinkhorn (Phallus ravenelii) is a common and widespread mushroom in gardens, lawns, meadows, cultivated areas, and woodlands of eastern North America. It is found from August through October, singly or in clusters, on the ground or on well rotted stumps, logs, wood chips, or sawdust.

The fruiting body at first is white to pinkish and egg-shaped, resembling a puffball. When conditions are right the “egg” ruptures and expands rapidly, sometimes in as little as one hour, producing a 4″ to 6″ tall, distinctly phallic structure with a stalk and thimble-like head. The rapid expansion is possible because all of the parts are fully formed and compressed inside the “egg”, and because the individual cells elongate, rather than new cells being produced. As the stinkhorn expands the gelatinous layer mixes with the spore mass producing a shiny, putrid slime that covers the cap. The foul-smelling slime is irresistible to flies, which feed on it, lay their eggs in it, and transfer spores when they fly to other stinkhorns.

Like all stinkhorns, this mushroom is edible. However, the slimy consistency inside the “egg” and the putrid odor the mature mushroom are enough to dissuade most from collecting it for the table.

Crowded Parchment (Stereum complicatum)

Small Stagshorn (Calocera cornea)

Hairy Bracket (Trametes hirsuta)

Trametes pubescens

Honey Mushroom (Armillaria mellea group)

Long-spined Puffball (Lycoperdon pulcherrimum)