Midwest

American

Mycological

Information

Morchella americana
(aka Morchella esculentoides, previously known as Morchella esculenta, M. crassipes, or M. deliciosa)

M. esculentoides

M. americana

Common color variations

Common color variations

Common name: Common morel, White morel, Gray morel.

Description: M. americana is a commonly harvested spring mushroom which ranges in color from gray to whitish to yellowish. The fruiting body is medium to large (up to 5-22 cm or more tall). The sponge–like head is egg-shaped, oval to conical, or pine cone-shaped with pits and ridges that are primarily vertically arranged. On all forms the ridges are paler than the pits. The hollow whitish stipe is nearly equal, or enlarged toward the base, attached to the cap without a notable overhang or rim. When found with a stout and enlarged stipe base, yellow morels have been known as M. crassipes, but DNA evidence has shown these to be older yellow morels which have grown in optimal conditions of temperature and moisture.

Ecology/associated hosts: Morchella americana is possibly saprotrophic and mycorrhizal at different times in its life cycle. This morel is often found under hardwoods, especially ashes and recently dead elms, as well as aspens, balsam poplars, sycamores, tulip trees, and apple trees in old abandoned orchards. Occasionally this morel will be found associated with conifers, especially white pine.

Look-alikes: There are several mushrooms that fruit at the same time as morels, and that vaguely look like morels. For example, Verpa bohemica, the wrinkled thimble cap, and to some extent Verpa conica, the smooth thimble cap, bear some resemblance to the half-free morel. They are easily distinguished, however, as Verpas have folds on the cap and all morels have pits. Further, the stalk of the half-free morel attaches to the base of the cap, half way up the cap, leaving half of the cap hanging free like a skirt. The stalks of the Verpas, however, attach right at the bottom of the top of the cap. Almost the entire cap hangs free, skirt-like. Verpa bohemicas can more easily be confused with Morchella punctipes than the smooth capped Verpa conicas. Compare the sectioned Verpa bohemica with stalk attached to the bottom of the top of the cap, to the sectioned Morchella semi-libera with the stalk attached half way up the cap. Verpas are slightly poisonous and are not authorized for collecting and selling in Michigan.

Verpa bohemica

Verpa bohemica

Verpa conica

Verpa conica

Morchella punctipes

Morchella punctipes

Gyromitra esculenta, the false morel or the beefsteak morel, also fruits at the same time as morels. This mushroom has been responsible for many deaths in Europe, and several poisonings in the U.S. Chemical analysis has shown that this mushroom contains the chemical gyromitrin, which our digestive system converts into monomethylhydrazine, which is both a toxin and carcinogenic. While chemical studies have shown that the amount of gyromitrin present in any strain of Gyromitra can vary greatly, the effects can be so devastating that this mushroom should never be consumed. Unlike most morels, the stalk of the Gyromitra esculenta is many chambered. Yellow, black and half-free morels have a single chamber formed by the stalk and the cap. The burn morel has a multichambered stalk but is has pits on its cap whereas the beefsteak has wrinkles or folds.

Gyromitra esculenta

Gyromitra esculenta

Morchella angusticeps
(previously known as Morchella elata)

Morchella angusticeps

Common name: Common eastern black morel.

Description: Morchella angusticeps is generally the first true morel to appear in spring in Michigan. The fruiting body is up to 18 cm tall. The sponge-like head is variable in shape but usually elongated and pointed. The head has elongated and irregular pits with ridges that darken with age. The young black morel may appear almost white when covered by leaf litter, but the mature black morel will have brownish pits and dark ridges. The hollow whitish stipe is attached to the head with a slight overhang or rim. The stipe will darken to reddish brown as it ages.

Ecology/associated hosts: The black morel is mycorrhizal, and can be found under hardwoods, especially white ash and tulip trees, but also cherry, aspen and sometimes pines.

Look-alikes: Morchella septentrionales is a similar black morel, which occurs north of the 45th parallel in Michigan. This black morel is slightly smaller, found under hardwoods, and can be found fruiting from decaying wood of big-toothed aspen and white ash. It is probably saprophytic and mycorrhizal. As with all true morels, it is edible as long as it well cooked.

Morchella capitata

Morchella capitata

Common name: Burn-site morel.

Description: The hollow caps of Morchella capitata are from 4-8 cm tall, conical or nearly round. On mature caps the ridges are dark brown to black. The pits are primarily vertically elongated and brown to tan at maturity. The cap is attached to the stipe with a small groove. The white stipe is layered or chambered, especially near the base, even when immature.

Ecology: This morel is possibly saprobic and mycorrhizal at different times in its life cycle. M. capitata may appear in conifer forests the first year after a fire, but rarely two years after. This morel is edible, but often the sand and fire residue on the mushrooms make them of less value for sale.

Morchella punctipes

Morchella punctipes

Common name: Half-free morel.

Description: The half free morel has a cap (1-4 cm high) that is attached about halfway down the stipe and flares on the stipe in a skirt-like manner. The hollow cap is broadly conic with a round to blunt apex, and divided into pits and vertical ridges with secondary shorter horizontal ridges. The whitish stipe is (3-15 cm) high, nearly equal, enlarging downward and is hollow. The surface of the stipe is spotted with mealy granules that may darken with age.

Ecology: M. punctipes is mycorrhizal, solitary or scattered in hardwood forests or old apple orchards in the spring, fruiting a bit before the yellow morel. This species of half-free morel is found east of the Rockies. DNA of western collections differs from that of M. punctipes.

M. punctipes is edible. It should not be confused with Verpa bohemica that has the cap perched only at the top of the stipe, so that the sides hang completely free. V. bohemica has the stipe at least partially stuffed with a soft cottony tissue. Verpa causes gastrointestinal distress in some people and is best considered inedible.

Possible allergic reactions and cautions: Although most people can safely consume cooked morels, a few become allergic, and a few experience gastrointestinal distress. All morels should be cooked thoroughly and never served raw, as cooking can destroy the gastro-irritant. The black morel, M. angusticeps, has been reported to cause stomach upsets when consumed with alcohol.

Various Morchella species myco-accumulate lead from 70-100 times, so attention must given to selecting clean picking sites. It is best to avoid areas near hiways, golf courses, and industrial sites. An article by Elinor and Efrat Shavit in Fungi (2010) found lead arsenate used in old apple orchards in northeastern U.S. to be a contributor to morel toxicity. Always remember to eat only clean mushrooms, free of decay.

Tips on harvesting: Morels should be cut with a knife near the soil surface and cleaned of detritus with a soft brush before placing in a basket. If the mushrooms are cleaned as they are harvested, it will keep dirt out of the pits of those morels previously collected. As with most fungi, morels should be stored in paper bags or waxed paper and refrigerated soon after harvest. Do not store morels in airtight plastic bags or containers; they will last longer if kept from drying out, but allowed to breathe.



Photos:

Cross-section of M. esculentoides

Cross-section of M. americana

Morchella angusticeps

Morchella angusticeps

Morchella capitata

Morchella capitata

Fluted stipe of M. capitata

Fluted stipe of M. capitata

Morchella punctipes

Morchella punctipes

References:

Bueg, M., Bessette, A, Bessette, Arlene. 2014. Ascomycete Fungi of North America: a mushroom reference guide. University of Texas Press. 488p.

Kuo M. 2005. Morels. Ann Arbor: Univ. Michigan Press. 205p.

Kuo, M., Dewsbury, D.R., O’Donnell, K., Carter, M.C.,Rehner, S.A., Moore, J.D., Monclavo, J.M., Canfield, S.A., Stephenson, S. L., Methven, A.S., Volk, T.J. 2012. Taxonomic revision of the true morels (Morchella) in Canada and the United States. Mycologia 104(5):1156-1177, doi:10.3852/11-375.

Kuo, M., Metheven, A. 2014. Mushrooms of the Midwest. University of Illinois Press. Urbana, Chicago, and Springfield.

Rodgers, R. The Fungal Pharmacy. 2011. North Atlantic Books, Berkeley, CA. pp. 287-291.

Shavit, Elinor and Efrat. 2010. Lead and arsenic in Morchella esculenta fruitbodies collected in lead arsenate contaminated apple orchards in northeastern United States: A preliminary study. Fungi3(2):11-18.

Web Sources

Michael W. Beug. Poisonous and hallucinogenic mushrooms.

Kuo, M. (2012, November) The Morchellaceae: True morels and verpas.