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The Great Outdoors

An Ode To The Jack-O’-Lantern Mushroom, A Poisonous Friend

My slightly dried-out specimens one week after harvesting.
Photo by the author

You are walking through the forest on an autumn afternoon, eyes low, when out of the underbrush you spot a bolt of frilly, apricot-colored protuberances. You think you have found the chanterelle, among the most prized and popular mushrooms, described in the legendary All That The Rain Promises And More as the “queen seductress: fruity, peppery … complex, and very singular.” These ones are bigger and more orange-tinged than those you’ve seen in the grocery store, but they smell good and you’ve heard the chanterelle has no obvious poisonous lookalikes, so you eagerly harvest them, return home, and munch the mushrooms. But 20 minutes later, something happens. In your butt, that is. You have made the mistake of harvesting and eating the poisonous western jack-o’-lantern mushroom (Omphalotus olivascens), one of the most beguiling and mysterious mushrooms the fungal world has to offer.

Everyone seems to have gotten into mushrooms in the past two years. While pandemic-induced bouts of protracted inside time have led many to think, “I should buy a house in Boise,” the same circumstances have led many more people to go outside, walk around, and look at stuff. It follows that many of those people, myself included, would be drawn to mushrooms: I was fungipilled by Defector’s Giri Nathan. While many species have been meaningfully domesticated, one of the most seductive aspects of fungi is how they upend so much accumulated societal wisdom. They seem like plants, but are more closely related to humans than anything with leaves. They can break down the most toxic of substances, and pop up in the oddest of places (underwater, from this guy’s carpet, next to your houseplant). They can rejigger your brain. They can kill you. They are infinitely adaptable, only halfway understood, and they will probably outlive the human species. Seriously considering the networked ways they live and defy categorization presents new radical possibilities for organization and crisis resistance, an especially enticing trait in our time of collapse. Few species capture the essence of what makes the fungal kingdom so special like the jack-o’-lantern, which has incredible stats.

Last weekend, I went out foraging somewhere in Marin County, where I found clusters of oyster mushrooms (delicious), a few death caps (does what the name says), and a huge flush of jack-o’-lanterns. They were speckling a hill of dense oak woods, preferring dead stumps and downed wood over the open forest floor. Jack-o’-lanterns are the closest-looking poisonous mushrooms to chanterelles, but they can be easily distinguished by most foragers. They tend to grow in fused clusters, their flesh is never white, and they have thinner gills and different cap margins than the chanterelle. You should never eat anything you are remotely unsure of, though chanterelles truly are distinctive to even most novice foragers. Also, luckily, the jack-o’-lantern will not kill you. This guy’s account of a 2002 poisoning paints a sufficiently rich tapestry:

Everything seemed fine until about 20 minutes after the meal, when I was walking through the living room and suddenly felt like I had been kicked in the gut by a mule. The spasm was severe, and I dashed for the bathroom, barely made it to the commode, and had projectile vomiting with such force that it literally splattered all over the room. In the meantime, I was on my knees trying to throw up my socks when I started salivating like a rabid dog. At first, I used tissue to wipe my mouth, but soon, it was easier to just hover over the toilet and drool.

Wilderness and Environmental Medicine

The symptoms lasted for a few hours, after which this poor guy was fine. Fear of poisonous mushrooms is an appropriate and necessary starting place for the forager. You should not eat, say, any amanitas until you have ample experience distinguishing the delicious coccora from the death cap, and you shouldn’t undertake the intensive detoxification process of fly agaric caps unless you have David Arora himself on hand. The jack-o’-lantern is neither poisonous nor well disguised enough that you should stop plucking obvious chanterelles, though it demands appreciation. Also, to dismiss the jack-o’-lantern and steer clear of it entirely even after you can tell it apart from its edible friend would be to miss out on its subtle gifts.

Aristotle and Pliny the Elder each described a “cold fire” in the woods, which was at some point dubbed “foxfire” and turned out to be the glow of bioluminescent mushrooms. Jack-o’-lanterns still growing on their host stump will glow a neon green in the dark, though you need to let your eyes adjust for a few minutes before you can see the phenomenon (I needed to go home, so I didn’t see this). For a long time, scientists didn’t know why the 71 species of bioluminescent mushrooms put energy into glowing. There was no discernible biological benefit to emitting the relevant enzyme, which is called luciferase. In 2015, researchers discovered that bioluminescence can help mushrooms attract nocturnal insects, which aid in carrying spores when the forest canopy tamps down wind dispersal. Even then, this phenomenon is probably not universal, and researchers still are not completely sure about the mechanics of fungal bioluminescence. This is unbelievably enticing. Mushrooms, the fruiting bodies of mycelial networks, are neither controllable nor completely knowable, and there’s something special about a rare and somewhat mysterious occurrence like bioluminescence. This is also how jack-o’-lanterns get their names.

Perhaps now that you’ve learned about how jack-o’-lanterns A) make you crap, and B) glow in the dark, you have come to the reasonable conclusion that jack-o’-lanterns, beautiful as they are, offer nothing to the curious human but pain and mystery. This is not true. Look closely at a jack-o’-lantern and you’ll notice a faint, dark iridescence to the gills and cap margin. It’s almost purple, or deep olive. This shimmers hint at the jack-o’-lantern’s use: dyeing yarn. Despite its orangeness, the jack-o’-lantern can somehow give you purple or green yarn. The procedure is somewhat involved, but if done correctly, you can wring some real (non-psychedelic) magic from these mushrooms. I am drying mine out until I have access to an outdoor stove—the dyeing process produces somewhat toxic air—at which point I’m going to try for purple.

Appreciating each of the jack-o’-lantern’s three “gifts” (light, dyeing potential, doo-doo ass) necessitates a fully rounded fungal appreciation, which is why I like it so much. It’s more than just a poisonous beauty, or a misunderstood lookalike. It is a delightful contradiction.

Disclaimer: Seriously, do not eat this mushroom if you ever find it. All wild mushrooms should be identified in consultation with a guidebook, an expert, or both. This post qualifies as neither, and its intent is biological information, not foraging advice. If you think you have eaten a poisonous mushroom, call poison control immediately.