#034: Mushroom Morphology: False Morels
False Morels, despite their name, are easily distinguished from true morels simply by simply looking at them. If you are new to identifying false morels, there are three factors that set them apart from true morels: 1) false morels have a head that is wrinkled, rather than consisting of ridges and pits; 2) false morels have a head that is attached only at the top of the stipe; 3) and false morels have a stipe that is solid or filled with cottony material, rather than hollow. If you’re unsure whether you have a false or a true morel, just slice the mushroom from top to bottom and look for the three factors above. If you’re familiar with these two groups of mushrooms, then you can differentiate between them just by glancing at them. I think that false morels look kind of like melted versions of morels: instead of the upright head of a true morel, false morels have heads that are flopped over and lopsided, as if they had melted in the sun. False morels appear in the early spring, often in the same areas as true morels. In fact, the two groups of mushrooms can frequently be found fruiting relatively close together.
All false morels contain the toxin gyromitrin and should be treated as poisonous. Despite this, some false morels like Gyromitra esculenta have been eaten (especially in Europe) for a long time. Gyromitrin is a volatile compound and can be removed from the mushroom by boiling, allowing the mushroom to be eaten. However, there can still be some gyromitrin left in the mushroom, which may accumulate in your body over time. You can also become poisoned by the vapor from boiling the mushroom, which contains significant amounts of gyromitrin. Different patches of false morels have different concentrations of gyromitrin, so edibility of false morels varies by region. Despite this, I recommend against eating any false morel. The onset of symptoms of gyromitrin poisoning is delayed by 6 to 12 hours and can include: “nausea, vomiting, diarrhea, cramps, distention, weakness, lassitude, and headache; if the condition is severe, these may develop into jaundice, convulsions, coma, and death.”* Gyromitrin is also a carcinogen, so long-term exposure may raise the risk of cancer.
All false morels are contained in the genus Gyromitra. This genus is found in the Phylum Ascomycota, Class Pezizomycetes, Order Pezizales, and Family Discinaceae. Gyromitra species come in a variety of other shapes, but they are all variations on the basic false morel morphology. They all have a wrinkled head and a solid or cottony stipe, although in some the stipe is greatly reduced. Some Gyromitra species end up looking more like cups. Careful macroscopic observation is usually enough to separate species of Gyromitra, although microscopic analysis of the spores is sometimes required.
* more details on gyromitrin: http://botit.botany.wisc.edu/toms_fungi/may2002.html
See FFF#033 for more on true morels.