Minnesota Fungi

Hygroscopic Earthstar (Astraeus hygrometricus) is a late season, small or medium-sized mushroom—small when closed, medium-sized when open. The fruiting body looks like a puffball at first. As it matures the outer layer of the case splits into 6 to 15 pointed rays, exposing a nearly spherical spore sac. When fully expanded, it can be 3″ or more in diameter. When moist, the rays arch backward to the ground, raising the spore sac, and facilitating distribution of the dust-like spores. The rays sometimes have a pale foreground with dark cracks and crevices, appearing like dried, cracked mud in a dry lake bed. In dry conditions they fold back over the spore sac and become hard. At maturity, the spore case ruptures through a pore at the top, and the spores are disbursed by the wind.

Hygroscopic Earthstar has a global distribution. It is common in North America, Central America, and Europe, and has been collected in Africa, Asia, and Australia. In the United States it is common in the Great Lakes and coastal states, uncommon in Minnesota.

Hygroscopic Earthstar is similar in appearance to true earthstars but it is not even closely related. It is an example of convergent evolution, where species of different lineages evolve similar features. It is identified by the following characteristics: the rays are hygroscopic, expanding in moist conditions and covering the spore case in dry conditions; the upper ray surface is often pale with dark cracks and crevices; the lower ray surface is covered with matted, blackish, hair-like fibers; the spore case is stalkless, roughened by numerous particles, and ruptures through a single, poorly defined pore at the top; and the spores are very large, but this can only be seen under a microscope.

Purple-bloom Russula (Russula mariae) is a medium-sized gill mushroom. It is common and widespread in deciduous and mixed woodlands and forests of North America east of the Rocky Mountains. It is found from June through October, singly or in groups, on the ground near hardwoods. It obtains its nutrients from the rootlets of oak and other hardwood trees.

Purple-bloom Russula is easily recognized by the flat, dry, velvety or powdery, purple cap.

Mica Cap (Coprinellus micaceus) is a very common mushroom in Europe, Asia, Africa, and North and South America. In the United States is seen from coast to coast. It occurs from April through October in forests and woodlands, in suburbs, in urban areas, and sometimes indoors. It grows in dense clusters on decaying stumps and logs, and sometimes on the ground on buried wood.

When young, it is dome-shaped, yellowish-brown, and covered with glistening particles. As it matures it flattens out, the particles wash away, and the cap becomes gray at the margins. As the mushroom ages the cap turns black, the margins become tattered, and the gills dissolve into an inky black liquid that drops to the ground.

Cortinarius is the largest genus of gilled mushrooms. There are estimated to be over 1,000 species worldwide. The common name “Cort” used here refers to all fungi in the genus, most of which have no individual common name, many of which remain unclassified. Corts are identified by a silky or cobwebby protective veil covering the developing gills of the young mushroom; spores that are rusty-brown or cinnamon-brown; and their occurrence on the ground in woodlands.

The species Cortinarius atkinsonianus is common and widespread in eastern North America. It is found on the ground either scattered or growing close together (gregarious) but not in clusters. It is sometimes found in rings or arcs. It appears in the fall under or near hardwoods in deciduous and mixed forests and woodlands.

The cap is 2″ to 6″ in diameter and the stalk is 1½″ to 4¾″ tall. There is often dirt and debris stuck to the cap because it was slimy or sticky when it emerged from the soil. It is olive-yellow and convex at first. As it ages it flattens out and darkens to deep reddish-brown from the center outwards, with the margin remaining olive-yellow. The flesh is whitish to pale yellow with lavender or violet areas. It stains lavender or violet when bruised. Many Cortinarius mushrooms are poisonous. The edibility of this species is unknown, but due to the difficulty of identifying these mushrooms it is recommended that they are not eaten.

Orange-gilled Waxy Cap (Humidicutis marginata) is a medium-sized, easily identified mushroom. It is widespread in North America but not common in the Midwest and northeast. It grows on the ground in humus, sometimes on very rotten wood, in coniferous, deciduous, and mixed forests. It may be found singly, scattered, or in small groups. It is edible but insubstantial and watery.

Three varieties are recognized; var. marginata, with an orange cap; var. concolor, with a yellow cap, more common in the northeast; and var. olivacea, with a olive-colored cap, more common in the west. The variety in most common in Minnesota is identified by the bright orange color; the cap that appears watery when wet but is never slimy; and the orange gills that retain their orange color even long after the cap has faded to yellow.

Comb Tooth (Hericium coralloides)

Crown-tipped Coral (Artomyces pyxidatus)

Gabled False Morel (Gyromitra brunnea)

Cinnabar Polypore (Pycnoporus cinnabarinus)

Snow Morel (Gyromitra gigas)

American Eastern Yellow Fly Agaric (Amanita muscaria var. guessowii)

False Morel (Gyromitra esculenta)

Cedar-apple Rust (Gymnosporangium juniperi-virginianae)