Interest in foraging for mushrooms has, ahem, mushroomed in Maine in the past year. So too have cases of mushroom poisoning.

So what advice would Michaeline Mulvey, president of the Maine Mycological Association, give to people who are new to the hobby?

“Be very careful. Wild foods are not necessarily safe. Caution. Caution. Don’t have too much excitement. You need to have a jaundiced eye,” she said.

Membership in the association, a “nonprofit devoted to a better understanding of mushrooms and our environment,” has roughly doubled in the last year to some 700, Mulvey said. Likewise for participation in the association’s outings. While many were canceled this past summer because of rising numbers of COVID-19, one outing in late July drew more than 60 participants, another in early August more than 70. Typically, Mulvey said, the group’s outings attract 10 to 30 members.

What accounts for the surge?

A dotted stalk suillus, an edible mushroom, that Jean Yarbrough found near her home in Harpswell. Yarbrough has been avidly foraging for mushrooms for more than a decade. This year, many others in Maine have become interested in the activity. Derek Davis/Staff Photographer

Possibly the agreeable – from the mushroom’s point of view, anyway – weather, just the right degree of wet. “It’s a phenomenal year,” Mulvey said. “There hasn’t been a year like this for five or more years in most parts of the state.”

Add to that, the pandemic. Mainers have been advised to get out-of-doors and to keep away from big gatherings. Foraging in the forest seems like an ideal pandemic pastime. At the same time, pandemic disruptions in grocery store supply chains have spurred interest in securing one’s own food supply, at least that’s the idea, by buying local food, growing vegetables and foraging. And don’t forget the rising popularity of “goblincore,” an aesthetic that celebrates woodsy, funky nature – mushrooms included.

But ingesting the wrong mushroom is no joke. Problems range from upset stomach, vomiting and diarrhea to seizures, rapid heartbeat, liver failure – and death. The most important and oft-quoted rule for foragers: When in doubt, throw it out.

Karen Simone, a clinical toxicologist and director of the Northern New England Poison Center, said the number of mushroom-related poisoning cases in Maine has climbed this year. From 2018 through 2020, the average number of cases for “little kiddos going out into the yard and finding something interesting and taking a bite” was 30. “So far this year, we have 36 cases already (none deadly), and we are not done with the year yet,” she said.

“If there are a lot of mushrooms outside and a lot of children outside, the two will meet and it’s not always a good thing,” she said.

Looking at the same years for adults, and limiting the data to mostly foragers, Simone said the center tracked not quite 20 adults in Maine a year for mushroom poisoning (also not deadly) in the years 2018, 2019 and 2020. “This year in adults, so far we’ve had almost 30 cases, which is a 50 percent increase in adults.”

“It’s a good mushroom year,” Simone continued. “People are excited about foraging, and I do think this COVID has something to do with it. But being excited is one thing. Being well-versed in what you are doing is a whole other thing. From my perspective, I’d rather people limit their foraging to the grocery store because I know it’s safe.”

Not dissuaded? We asked Mulvey for some mushroom foraging basics.

HOW TO START: Get a good field guide with a good introduction to the identification system for wild mushrooms. Do this before you participate in an outing like those organized by the Maine Mycological Association. Those outings typically start outdoors with participants gathering in the woods around a table covered in mushrooms, which they discuss and try to identify.

“If the first thing they do is look at a table full of 30 to 50 mushrooms, they are not going to be able to make sense of them. The first time people come to those, I try to tell them to learn a few things and leave before it becomes overwhelming.”

WHEN TO GO: Generally speaking, Maine’s mushroom season extends from July into the fall. September is peak season. Typically, mushrooms start to fruit 10 days to two weeks after a good rain.

WHAT TO WEAR: There’s no single answer. “Some people tuck in their pants legs for ticks and poison ivy, and some people know what poison ivy looks like and figure they can see the ticks crawling up their legs so they wear shorts.”

WHAT TO BRING: A knife to dig up any mushrooms you forage. It’s important to get the entire mushroom, including its underground base, in order to ID it correctly. While dedicated mushroom knives exist – they fold and come with brushes at the base to clean the mushrooms – Mulvey herself is no gear geek. She uses her fingers to harvest, and says spoons or kitchen knives will also work.

A paper bag or basket to carry any mushrooms you gather. Mushrooms are delicate; for that reason, a square-bottomed bag with handles is “a little bit better than something you crinkle and roll up the top.” You’ll also want smaller bags to sort your mushrooms, separating edible mushrooms from non-edible most importantly, as well as mushrooms by species. Do not use plastic, which will make the mushrooms sweat.

WHERE TO GO: To forage on private land, you need permission from the landowner. By law in Maine, hunters may hunt on private land unless the land is posted. But unlike wildlife, mushrooms stay put, so they belong to the landowner, Mulvey said. (Even for hunting, the Maine Department of Inland Fisheries & Wildlife strongly suggests you follow what it calls “the unwritten rule,” namely, “Always ask permission.”)

It is illegal to forage for mushrooms in state parks.

COME HUNGRY: Among the edible mushrooms you may find in Maine woods or fields are – Mulvey lists them seasonally, starting with spring – oyster mushrooms, chanterelles, black trumpets, cepes (including porcini), puffballs, hen of the woods and matsutake.

“Many foragers simply want to learn their five, 10 or 15 edibles, and that’s all they want at the end of it.” Others are interested in natural history and want to learn the whole spectrum.

PORTION CONTROL: Some foragers harvest every mushroom they see, behavior Mulvey considers impolite or even unethical. Their attitude is, according to her, “If I leave some, someone else will know where they are. It’s a greediness that I don’t like to see.” Mulvey suggests foragers leave 30 to 50 percent of mushrooms they harvest so that the remaining mushroom can do its job, namely reproduce. (The mushroom is the fruiting body of underground fungi. It reproduces by spreading its spores.) Don’t divvy up individual mushrooms by percentage; rather, harvest that percentage of a mushroom cluster.

Mushrooms “are not ours, but they belong to the environment. The natural world is depending on them, too.” Among the wildlife that eats, or otherwise needs mushrooms, are flying squirrels, deer, and fungus gnats.

So we really need to leave mushrooms we’d like to eat for the gnats? “They are a part of nature. Do we want to encourage mosquitoes? They are not good for us, but they are food for the phoebes and the flycatchers. Why would we want to wipe them out?”

MUSHROOM ETIQUETTE, PART 2: “There is an ethic I try to teach people: This is my patch of mushrooms. If you find this patch on your own, it’s our patch of mushrooms. If I show it to you, it’s still my patch.”

DEVELOP YOUR SKILLS: What makes a good forager? First, enjoyment of the outdoors whatever the outcome of any one outing, because “you don’t always find something.” Next, good powers of observation. Foragers need to note, for starters, “where the mushroom is growing, how it’s growing, what it’s growing with, whether it grows high on a tree or low on the ground, whether it likes oak trees, whether it grows in a coniferous forest or a deciduous forest.”