Mushroom Monday
Mower's Mushroom (Panaeolus foenisecii)
Good evening, friends,
This week’s mushroom is the Mower’s Mushroom (Panaeolus foenisecii). I encountered this mushroom a couple times over the weekend and the first find was on Friday down at the New York Botanical Gardens. I went to check out their new Wonderland: Curious Nature installation which is a botanical adaptation of Alice in Wonderland. Mushrooms had a nice place in the installation as well as the rest of the grounds where they were spontaneously popping up in the grass.
Fun Facts
In older literature it was thought that these mushrooms were psychoactive and contained psilocybin. Perhaps they were confused with Psilocybe semilanceata, or as Paul Stamets notes, the closely related and psilocybin-containing Panaeolus cinctulus. All three of these mushrooms are LBMs (Little Brown Mushrooms) that grow in grass.
You can also find these mushrooms listed as toxic, inedible, or edible depending on where you look. A study from Switzerland (Reference 3) found there were “no clinically relevant effects” from children accidentally ingesting these mushrooms, and in that Stamets’ video above he says he ate 50 of them to see if they had psilocybin. He also found no clinically relevant effects. For such a ubiquitous mushroom there’s a lot of uncertainty and lore surrounding them.
The cap is hygrophanous which means it changes color and develops lighter bands of color as it ages/dries out. That wasn’t the case in the above specimen as it was pretty fresh, but it did have some vertical striations at the bottom of the cap which might be the first signs of drying. The latin Panaeolus means “mottled” (which means spotted) but doesn’t refer to the cap - it refers to the gills which can have spotting on them because the basidia (the organ where the spores are released) don’t mature at the same time.
Ecology
P. foenisecii is saprobic and decomposes organic material in lawns - in theory dead grass roots. I also saw this mushroom in suburban CT and tried to observe whether they had a preference for lawns that were entirely grass (no clover, plantain, or other small plants likely due to herbicide) or lawns that weren’t as meticulously curated - but it seemed like the fungus was comfortable in both.
The mushrooms grow in North America and Europe, but I imagine (and iNaturalist suggests) they have a cosmopolitan distribution and can be found wherever there are mowed lawns. They fruit spring through fall.
Other Weekend Activities
I had a blast yesterday setting up a grow-your-own-mushroom/fungal education station for the Darien Land Trust at their adventure day for kids. When I got there, I walked three steps into the woods before I looked down and saw some mushrooms growing right in the wood chip trail. I crouched down, flipped one over, and saw lots of blue - more Psilocybe ovoideocystidiata mushrooms. They added a different dimension to the education station. And shoutout to the one dad who brought me a handful to confirm the ID and then left with them - I won’t tell mom.
And here are a couple pictures from the New York Botanical Gardens:
Going to New Hampshire over MDW, excited to see and share what’s growing in the Whites,
Aubrey
References
Kuo, M. (2018, February). Panaeolus foenisecii. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/panaeolus_foenisecii.html
https://www.first-nature.com/fungi/panaeolina-foenisecii.php#etymology
Schenk-Jaeger KM, Hofer-Lentner KE, Plenert B, Eckart D, Haberl B, Schulze G, Borchert-Avalone J, Stedtler U, Pfab R. No clinically relevant effects in children after accidental ingestion of Panaeolina foenisecii (lawn mower's mushroom). Clin Toxicol (Phila). 2017 Mar;55(3):217-220. doi: 10.1080/15563650.2016.1271129. Epub 2017 Jan 11. PMID: 28073319.
https://www.inaturalist.org/taxa/902551-Panaeolus-foenisecii
https://explore.beatymuseum.ubc.ca/mushroomsup/P_foenisecii.html