Though winter salt’s effects on the city are numerous — de-iced sidewalks, salt-splotched cars, canines sporting booties or cradled in the protective arms of owners — less immediately obvious is the impact on the natural environment, including the fungi underfoot. One byproduct of road salt may be the surprise appearance of autumn Agaricus bernardii, a relative of the white button mushroom found in supermarkets, long after all the snow and ice of the previous winter has melted.
Last October, I found several curious Agaricus specimens, with pinkish-beige, heavily cracked caps that were as large as my outspread hand, growing along an inner road at my college campus on Staten Island. As the Agaricus genus includes many poisonous species, I collected several samples over the course of the month to show senior members of the New York Mycological Society.
The mushrooms caused puzzlement and then excitement: this variety of Agaricus, A. bernardii, is uncommon in the city, and when it does show up, it didn’t necessarily appear again in ensuing years. The freshest fungi, with thick stubby stalks and caps as robust as portobellos, were looked upon with admiration and a bit of foodie-lust by my fellow mycological enthusiasts.
When available, Agaricus bernardii can be found in seaside areas in Europe, and along both United States coasts, where it seems to favor salty, alkaline environments like sand dunes or sandy soil along roadsides that see a generous spraying of salt in heavy winters (like my college campus). Seasonal in summer and fall, it is also a winter mushroom in California, where it’s been most heavily researched. When fresh, A. bernardii bleeds red when cut (in my case, a subdued reddish-orangey-pink), and has a deep, velvety, chocolate brown spore print and a rich, briny odor that some find fishy.
One distinguishing characteristic of A. bernardii is the odor. The mycological society’s vice president, Dennis Aita, who has only ever seen it twice, in New Jersey and the Bronx, said, “the briny smell is unique, such that a blind man could probably identify it by its smell alone.” Another senior member warned against consuming any Agaricus species that had a coal-tar scent. (Even though my sense of smell is largely hampered by allergies, I buried my nose into the mushroom’s fleshy parts and caught a whiff of the ocean).
Mushrooms of the Agaricus genus, which includes the portobello, the baby bella, the crimini and the most commonly grown mushroom in the United States — Agaricus bisporus, a k a the white button — as well as poisonous ones that wreak gastrointestinal havoc — such as A. xanthodermus and A. placomyces — are notoriously difficult to identify. I would never dream of doing so on my own, even now. As with all wild mushrooms, always a) consult experts or their books, providing fresh samples whenever possible for them to study b) make spore prints c) proceed with caution before eating.
Once Aita proclaimed my mushrooms “choice!” I took them home and sauteed very thin slices in butter and a touch of white wine. Like a white button mushroom, my A. bernardii yielded a lot of water in the pan, which I allowed to burn off. The result — Agaricus bernardii on toast —was a slightly fleshier-than-expected mushroom experience.
This snowy winter, the city has already run through its entire salt budget.
Next fall, if A. bernardii comes up again, I’m going to grill it with goat cheese and guacamole.
Ava Chin is a professor of creative nonfiction and journalism at the College of Staten Island. The Urban Forager appears every other Saturday.