Gyromitra californica

Submitted by daniel on Wed, 05/18/2016 - 13:20

During a hike along gorgeous Boulder Creek in old growth forest not too far West of Darrington WA we found these beautiful ascos, Gyromitra californica aka Pseudorhizina californica. These Umbrella False Morels or California False Morels were growing along small creeks feeding into Boulder Creek in stands of Hemlock (Tsuga heterophylla), Sitka Spruce (Picea sitchensis) and some true firs (Abies sp.) in about 750 ft above sea level. I was fascinated by their structure, especially their stem ribs and how they shaped the cap and the purplish stem base.

I could not find any information if anyone had previously tested it for edibility. Raw they should be toxic like many ascos, i.e morels (Morchella spp.). The question is, are they as toxic as some of their close relatives in the Gyromitra genus, like the European Gyromitra esculenta, which can be deadly when eaten raw due to its gyromitrin content, a water-soluble hydrazine compound hydrolyzed in the body into monomethylhydrazine (MMH), a cancerogenous compound used in rocket fuel. Also poisonings happen when inhaling its off-gassing MMH while cooking or eating it seriously undercooked. 

Now, why would anyone in their right mind ask, are these Gyromitra californica fine to eat when cooked properly? Well, Gyromitra esculenta is very popular in Finland and Finish mushroom connoisseurs insist it is only a question of proper preparation. Furthermore, there are plenty of people who eat Gyromitra in North America, but some still get sick, see the detailed NAMA report by Beug et al. (2006) on mushroom poisoning in North America from the last 30 years. And in Western North America poisonings are even rarer.

Furthermore, taxonomically speaking Gyromitra californica is located in a clade with Ps. sphaerospora that seems not to contain Gyromitrin or very small doses. However, there is no conclusive data available. It is very hard to measure a volatile compound from an organism collected in teh wild that needs some time making it to a lab. Anyway, so far there are no poisoning reports in the NAMA database regarding Gyromitra californica, but that does not mean they did not happen. Dr. Michael Beug who keeps track of poisonings for NAMA does not recommend trying it out, which seems sound advice.

Anyway, I ate at first a tiny amount I had cooked very well and really enjoyed it, actually more than expected, nutty taste and a good chewy consistency. And my liver did not complain, not that one can feel short term liver trouble. I ate a few of them three days later, well cooked again and it has been 48 hours since I wrote this. However, I am done with that, it is just not worth my precious organs and I have less questionable mushrooms in the freezer I can enjoy. If you have had experiences with this mushrooms I am curious to hear about that, but I do not want to encourage anyone to try them out.

Gyromitra Pseudorhizina californica Umbrella False Morel
Umbrella False Morel or California False Morel, note the widely spaced ribs that extend into the underside of the cap.

Pseuorhiza Gyromitra californica 

Gyromitra californica


Beug, Michael W. 2014. Gyromitras, Which one is it and Can I Eat It? In: The Mycophile vol. 54.2, p.16-18, 20.

Michael W. Beug, Marilyn Shaw, and Kenneth W. Cochran. 2006. Thirty plus Years of Mushroom Poisoning: Summary of the Approximately 2,000 Reports in the NAMA Case Registry. From summary at

Last edited on Thu, May 19, 2016, 10:33 am