Morchella sp. — Morels

In true morels, the outermost surface of the head has narrow, flattened ridges that form rims around deep pits. Cut a morel in half; a hollow space runs from the inside of the cap to the base of stem. Do not confuse poisonous False Morels (indicated in the small images above), with brain-like rounded lobes or a saddle-shaped head, with edible true morels.

Odour: Mild, taste (always cook thoroughly and enjoy in moderation!) meaty, nutty, delicious.
Head: ~3.5-8 cm tall (varying by species) roughly conical, with deep pits rimmed by ridges, beige, tan, brown, or almost black. Cut the fungus lengthwise to verify that it is hollow from just under the tip of the head down most of the length of the stem. In most species ridges and pits up connect to the stem so that the whole cap is 'glued' to the stem along its entire length. In Morchella populiphila, a species associated with poplar trees along rivers, the bottom of the head hangs free as a skirt but at least the top cm or so of the cap is 'glued' to the stem.
Stems: 3-7 cm long x 2.5-4 cm wide (varies by species, occasionally longer or wider). Usually lighter than the head, whitish to tan.
Spores: 25-37 x 15-23 µm, contents homogenous without prominent oil droplets.
Habitat: On ground in forests. Black morels occasionally pop up in wood mulch and species of black morels can be abundant in spring following a forest fire.

The many species of morels share the same general shape and all are considered edible for most people, after being cooked. Gyromitra and Helvella species resemble morels in size and colour but have lobed or saddle-shaped heads. Gyromitra and Helvella species contain toxic, carcinogenic monomethylhydrazines4 and eating them involves substantial risk. Verpa bohemica resembles morels but the head is attached only at the top of the stem. Verpa species are more likely than morels to cause gastrointestinal upsets. Canned and dried morels have sometimes been contaminated with Gyromitra or Verpa, resulting in at least one serious illness and leading the US Food and Drug Administration to check and refuse import of batches of morels contaminated with these other fungi5.

Although widely appreciated as edible species, morels have caused a surprising number of gastrointestinal upsets, sometimes accompanied by neurological disorders6. From 1985-2006, 146 cases of poisoning were tallied in a North American Mycological Association report7. Eating raw morels, large quantities of morels, or morels that were old and perhaps contaminated with bacteria apparently contributed to poisonings in some, but not all cases6. Evidence for an interaction of alcohol with morel poisoning is equivocal.

Toxins: Unclear, gastrointestinal symptoms may be due to hemolysins, which damage red blood cells but presumably usually evaporate or are destroyed by cooking6.
Symptoms: Most common symptoms are gastrointestinal (67%)6. From ~15 min to 13 h after eating morels, symptoms include nausea, vomiting , cramps, and diarrhea. Neurological symptoms arise 2 h to 1 day after eating and include vision disorders, dizziness, drowsiness, hand tremors disorientation, numbness and sensitivity to sound, chills. Most people recovered within a day, although in one individual, tremors lasted for a month 6.
Treatment: It is important to distinguish whether morels (Morchella sp.) or false morels (Gyromitra sp.) caused poisoning sympotms. Initial gastrointestinal symptoms may be similar, but poisoning by false morels justifies hospital admission as it can lead to kidney and liver damage, seizures, coma and death. Poisoning by morels usually resolves itself with supportive treatment or time.

Cases of poisoning from morels: In an infamous retirement banquet for Vancouver's chief of police, one of the city's best hotels served a pasta salad containing raw morels that poisoned 77 of the 483 attendees8. Victims reported nausea, diarrhea, vomiting, and cramps. Some reported a hive-like rash, not a usual symptom of poisoning by morels but possibly attributable to another raw mushroom, the shiitake Lentinus edodes, also in the salad.

UBC. University of British Columbia Herbarium Database, <> accessed May 1 2017.

Kuo, M. et al. Taxonomic revision of true morels (Morchella) in Canada and the United States. Mycologia 104, 1159-1177, doi:10.3852/11-375 (2012).

Arora, D. Mushrooms Demystified. Pp. Ten Speed Press, Berkeley CA (1986).

Berger, K. J. & Guss, D. A. Mycotoxins revisited: Part II. J. Emerg. Med. 28, 175-183, doi:10.1016/j.jemermed.2004.08.019 (2005).

Gecan, J. S. & Cichowicz, S. M. Toxic mushroom contamination of wild mushrooms in commercial distribution. J. Food Prot. 56, 730-734 (1993).

Saviuc, P., Harry, P., Pulce, C., Garnier, R. & Cochet, A. Can morels (Morchella sp.) induce a toxic neurological syndrome? Clin. Toxicol. 48, 365-372, doi:10.3109/15563651003698034 (2010).

Beug, M. W., Shaw, M. & Cochran, K. W. Thirty-plus years of mushroom poisoning: Summary of the approximately 2,000 reports in the NAMA case registry. McIlvainea 16, 47-68 (2006).

Kroeger, P. 'Yumm,' said the police chief. Mushroom The Journal 34 (1991).