Minnesota Fungi

Milk-white Toothed Polypore (Irpex lacteus) is widespread in Europe and North America. It is very common in the eastern United States to the Midwest, including Minnesota, but rare in the Southwest. It is exceptionally resistant to pollution toxicity. It grows on the bottom and sides of logs and fallen branches of hardwood trees.

The fruiting body is a stiff, dry, flat, spread out patch of spore surface attached directly to a branch or log. When growing on the side of a log or branch it may develop shelf-like, ⅜″ to 1½″ wide caps. The white, off-white, or cream-colored patches often fuse together creating a long row. There are 2 or 3 pores every thirty-second of an inch. The pore walls are thin and disintegrate unevenly. Eventually, only flattened, tooth-like projections less than ¼″ long remain. The flesh is thin and tough. It is not edible.

Velvet Foot (Flammulina velutipes) is a late season, cold weather, gill mushroom. It is extremely widespread, occurring throughout Europe, across North America, and in Japan. It is fairly common in Minnesota. It appears in the late fall in deciduous and mixed forests and woodlands. It grows in dense clusters on stumps, logs, and living trunks of hardwoods, especially elm. The cap color is somewhat variable. It may be reddish-brown, yellowish-brown, orangish-brown, or yellowish-orange. As it matures, the stalk develops a dense covering of dark velvety hairs beginning at the base and progressing upwards.

In 1993, Velvet Foot mushrooms were grown on the space shuttle to test the effects of zero gravity. As expected, the mushrooms grew in all directions. A Japanese cultivar of this mushroom, known as Enokitake or Enoki, is white and grows in dense clusters. It has very small caps and very long slender stalks. To achieve this, it is grown in complete darkness in a carbon dioxide rich environment. Producing more than 300,000 tons per year at the end of the twentieth century, it is one of the six most actively cultivated mushrooms in the world.

Witch’s Hat (Hygrocybe conica) is a small waxcap mushroom. It is common in Minnesota in deciduous and mixed woodlands. It grows on the ground in damp soil, alone, scattered, or in groups under hardwood trees, especially oak. In other areas it is also found under conifers and in grasslands.

When it first appears the cap is sharply cone-shaped and usually bright orange, sometimes bright red. As it ages fades to yellow or orangish and flattens out but retains a pointed raised center. Older caps develop black areas and eventually turn completely black. All parts of the mushroom turn black when bruised. The stalk usually grooved, often twisted, and never slimy.

Witch’s Hat was once considered poisonous due to four reported deaths in China, but those reports are now thought to be mistaken. It may be somewhat psychoactive. Eating it is not recommended.

Devil’s Stinkhorn (Phallus rubicundus) is native to the subtropical region of northern Africa, Australia, South America, northern Mexico and southern United States. It has spread throughout the eastern United States, probably in wood chip mulch imported from those regions. It is now common east of the Great Plains. It is found from spring through summer in lawns and gardens, especially where wood chip mulch is used. It grows on the ground, in wood chips or sawdust piles, singly or in groups.

The fruiting body at first is whitish to pale brown and egg-shaped, and resembles a puffball partially submerged in the ground. Inside the “egg” there is a gelatinous layer, a spore mass, and all of the fully-formed parts of the mature stinkhorn. When conditions are right the “egg” ruptures and expands rapidly. In one or two days it produces a 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.

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.

Handsome Club (Clavulinopsis laeticolor)

Cort (Cortinarius atkinsonianus)

Chaga (Inonotus obliquus)

Painted Suillus (Suillus spraguei)

Orange-gilled Waxy Cap (Humidicutis marginata)