In a wooded part of Fresh Pond Reservation in Cambridge, Larry Millman trudged forward, ignoring the low branches tugging at his coat.
He was on a mission to find mushrooms, taking advantage of the relatively mild temperatures (just over freezing) and light snowfall that made it easier to spot fungi. Most mushroom enthusiasts wrap up outdoor mushroom walks by the late fall. Not Millman.
"You have to look harder for things now, but you're still going to find them," he said.
To hunt for fungi in the winter, Millman recommends turning over logs and brushing aside leaves.
"Think of the leaves and the logs as parkas. And essentially, you're stripping away the parka to expose what you're looking for," he said.
Millman has been recording fungi here since 2005. So far, he's counted 399 different species. His goal is to document the diversity of fungi at Fresh Pond, where thousands of joggers, baby carriages and dogs carry in mushroom spores from near and far.
After mere minutes of looking that December day, and just a few feet into a wooded area off the walking path, Millman spotted tiny white squares encrusted on the side of a log. This species, Xylobolus frustulatus, is nicknamed ceramic parchment because it grows in a pattern like bathroom tiles.
It's not a recognizable mushroom shape — it looks more like crusty, dried paint. Not all fungi are mushrooms, which are the reproductive parts of some fungi species. And not all mushrooms have those domed tops, like the type you can buy in grocery stores. Most of the fungi Millman has found here at Fresh Pond aren't edible, either. He's in it for scientific curiosity.
He describes fungi in terms of their "charisma," almost like each one carries a unique personality. And he said a crust fungus like ceramic parchment might seem plain to the naked eye, but under the microscope there could be weird-looking spores or other features "that are totally charismatic," he said.
But he's encountered this fungus before, so it won't be the species to push his list to 400.
“I feel like he should almost be the Wikipedia image for the article of mycologist."Tim Puopolo, former park ranger
Millman is an avid mycologist and author of four books on fungi.
"I don't develop a sort of semi-interest in something. I either am passionate about something or not interested in it at all," he said.
He says he's always felt like an outsider, and that has led him to pursue overlooked and obscure things. He recalled a pivotal moment years ago at a cabin in North Carolina.
"One night we looked out the window and there was something glowing in the dark outside. And it was a bioluminescent mushroom called the jack-o'-lantern. And that itself was an epiphany for me. It lit up my life, so to speak," he recalled.
Millman has a reputation of being a dedicated collector and wealth of knowledge.
"I feel like he should almost be the Wikipedia image for the article of mycologist," said Tim Puopolo, a former Cambridge watershed protection ranger at Fresh Pond who helped Millman keep track of fungi in the park.
Once, Millman asked Puopolo to collect owl pellets — regurgitated balls of bone and fur — so that he could check them for rare fungi spores.
The pellets didn't yield any fungi, but Puopolo said it opened up his eyes to the world of mushrooms. Most park rangers specialize in plants or animals, he said, but the fungi kingdom is separate.
"So sometimes it's a big gaping hole in knowledge, especially when there's so many," Puopolo said.
Millman has always been interested in overlooked places, and Fresh Pond fits that category. Not because it's obscure or remote, but because its urban location is unassuming as a diverse place for fungi.
On his December hunt, Millman found several more species that have adapted to the New England winter, and can freeze and rehydrate throughout the season depending on the conditions. Each one he's seen before: Phlebia tremellosa, also known as trembling Phlebia, a wrinkly, orange mushroom found on dead wood; Stereum complicatum, also known as crowded parchment, a common fungus that's important for recycling nutrients and breaking down dead plant material; Chlorosplenium chlora, also known as yellow cup fungi, a cousin of the morel; Trichaptum biformis, also known as purple-toothed polypore, which looks like a seashell striped in violet; and Stereum ostrea, also known as false turkey tails, striped in brown and tan and growing prolifically on the bottom of a fallen tree.
Millman's keen eye also spotted fungi that lesser experienced hunters may miss. He pointed to a gelatinous substance on a tree branch: witch's butter. He's recorded three different members of the Exidia genus at Fresh Pond: white, brown and black witch's butter. Other types of witch's butter can be yellow, which carries particular significance.
"It was once thought in Eastern Europe when you saw some of this near your house ... that you had been cursed by a witch," Millman explained.
Millman donates many of his samples to Harvard University's Farlow Herbarium, which has plant specimens from Fresh Pond going back to the 1880s. Millman's donations add unique records to this history.
"He likes to collect throughout the season, which is something that not all mycologists do," said Don Pfister, a Harvard research professor and former herbarium curator. "We don't think of fungi as being prevalent in the winter, but he almost always finds something."
On that December hunt, Millman spotted a yellow mushroom ballooning out of a dead branch. He tore off a piece, then safely stowed it away in a plastic container so he could take it home to examine under a microscope.
He was also excited about a tiny white fungus called Lachnum virgineum, or hairy fairy cups.
"Look how delicate they are," Millman said. "And yet, they're doing just fine in the cold weather. While certain members of the Homo sapiens species are shivering half to death."
And to avoid that frigid cold, most mycologists will take their research inside for the winter. By contrast, Millman will be out at Fresh Pond hunting for that 400th species.
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