Yet it can be difficult to champion an organism that grows out of poop or decaying wood, can be deceptively toxic, and appears extraterrestrial. Stamets says American society is pervaded by "mycophobia"—an irrational fear of fungi that he traces back to England, whose medical tradition equates mushrooms with decay and decomposition. Stamets has little patience with those who disrespect mushrooms. "I hate the word 'shrooms,'" he says. "Pet peeves: Don't kick mushrooms in my presence and don't use the word 'shrooms.'"
The summer dry season has subdued the mushroom population, but as we walk and my mind becomes more focused they soon pop into view: bracket fungi growing like ledges across a fallen log, a fragile cup-capped mushroom camouflaged in leaf litter. Logging has razed the Pacific Northwest's old growth; less than 20 percent of the original forest is still standing. A handful of mushroom species, including agarikon, depends on this diverse habitat, whose disappearance Stamets views as not just a lost opportunity but a national security concern. The cancer drug Taxol was derived from the bark of Pacific yew trees, a conifer native to the Northwest. (See "Natural Selections.") And tests of 18 of the 28 strains of agarikon Stamets has cultured have found varying levels of antiviral potency, indicating the great diversity even within a single fungus species, adding to the urgency of protecting its dwindling habitat. It's conceivable that the most powerful strain is growing on a tree in a logging concession somewhere.
Foresters long assumed agarikon caused trees to rot, and preemptively logged them. Stamets, however, believes it actually protects trees from parasitic fungi. "The tree says, 'I will accept you, Mr. Agarikon, but I want you to protect me. Give me life, and I will give you my body.'"
In the weeks before our cruise, the National Center for Natural Products Research identified the structures of the molecules responsible for agarikon's antiviral properties. It found the molecules to be more active in the laboratory than the smallpox antiviral Cidofovir. Reverse engineering mushrooms' complex chemical creations to synthesize a new drug is a slow and costly process; Stamets estimates that he's sunk more than $400,000 of his own money into the effort. The next step toward developing a pharmaceutical is mammal studies, a gamble that the venture capitalists he has met with are so far unwilling to fund.
"I've seen the lab results. I know it has potential," says Rasmussen of INSTEDD. "What I don't know is how it performs in clinical trials. And that's a deeply frustrating situation to be in—to see this level of activity against nasty bacteria and viruses and not have the ability to begin clinical trials and work up the scale to human trials and see what the most effective delivery method is, what the dosing needs to be, what the side effects will be—and I think there will be very few. I mean, it's a mushroom, for God's sake." Thus far, the active ingredients in agarikon show no or very little toxicity.
Stamets has long had a hunch that agarikon could be a pharmaceutical powerhouse. He knew from historic texts that other cultures had tapped into its medicinal properties. In the year 65, the Greek physician Dioscorides described it as a treatment for "consumption"—an early name for tuberculosis. A 19th century British text noted that it was still prescribed "to diminish bronchial secretion."
Agarikon was also highly valued by the Coast Salish First Nations peoples of British Columbia. The Haida of British Columbia's Queen Charlotte Islands are said to have carved the tough, leathery fungus into spirit figures and placed them on the graves of shamans to protect them from evil spirits. Mushrooms also figure prominently in Haida mythology: Women, it is said, came into existence after a "Fungus Man" found shells that resembled vaginas. The Haida knew that boiling agarikon, which they called "ghost bread," into a tea helped with lung problems.
Tragically, they never discovered what Stamets is now finding: that the mycelium running through the tree bark is resistant to smallpox, which decimated the Haida when the British brought the virus to the region in the late 1700s. A few years ago, Stamets visited the Haida Nation's president. Oral traditions had kept the mushroom's reputation alive, but its secrets had been forgotten. "I know my grandmother knew about this fungus," the Haida leader told Stamets, "but after the smallpox epidemic we lost all of our elders, and we lost all of this knowledge."
AS THE MISTY ISLES sails alongside East Redonda Island, all binoculars on deck look for snags—craggy treetops that indicate an old, decaying Douglas fir, agarikon's ideal habitat. The captain, a Canadian named Mike, thinks we'd be interested in seeing some Haida pictographs on the northeast shore. The paintings come into view—crude red shapes on a granite face, sheltered by an overhang. Suddenly, from behind binoculars, a researcher yells, "There's one!" Our attention pivots toward a dense cluster of trees about 100 feet to the left of the pictographs, where I can barely make out a white blob growing on a Douglas fir.
"Oh my, it's huge!" Stamets cries. "It's like the Moby Dick of agarikon...the biggest one I've ever seen in my life! How cosmic, right where the pictographs are! God, you're a beautiful column. It's got to be 70, 100 years old."
Mike anchors Misty and I ride to shore with Stamets in an inflatable boat. We walk to the base of the tree and gaze up at the agarikon, 20 feet off the ground. The fungus is two feet long and resembles a bloated, mutant caterpillar, tubular and segmented. It is growing around a stubby branch poking out from the tree. Stamets believes that it probably fell from higher up, accidentally landed on the branch, and then calcified the wood to provide itself with a sturdy perch—an unusual occurrence he's never seen before.
From the pictograph site, someone calls out that one of the paintings appears to be of Fungus Man. "No way, no way!" Stamets exclaims. "Fungus Man is there? Oh boy, oh boy, I'm getting shivers up and down my spine now." He takes three deep breaths. "We may have discovered a mystery that no one ever knew—that the pictographs exist here because of agarikon. I feel like this is a fulfillment of a dream. We're so lucky. Unbelievable. See, this is the thing about mushrooms: It's not luck. There's something else going on here. We've been guided. But this is what happens. All of our big finds, we have been led." It also happens to be Stamets' 53rd birthday.
Stamets grabs a long stick and reaches up to poke the fungus. It won't budge. He pokes again. "We really shouldn't take it," he concludes. "We should be honored that we found it. This is now supersacred." He lets the agarikon be and walks over to check out the pictographs. Fading from time and the elements, the rock paintings depict a dolphin, a turtle, and a two-foot-high figure with stick arms, big round eyes, and what seems to be a mushroom cap growing out of its round head. Is it Fungus Man?
The afternoon sun is falling behind the island, so we leave the question unresolved and set Misty back on course. Just before dusk we reach the mouth of the Toba Inlet, a fjord carved into Canada's mainland, flanked by high slopes of Douglas fir, red cedar, and alder. We dock at a lone fishing lodge, and from an outdoor hot tub, we enjoy the tranquility that the salty George Vancouver once described as "an awful silence" pervading "the gloomy forest." Captain Mike grills salmon and Stamets considers the day's events. "I'm glad we didn't take it," he says. "When I had the stick in my hand, I felt, 'Something doesn't feel right about this.' I thought, 'If this is gonna come down just with a touch, I'll take it. But if it gives me resistance, I'm stopping.'" (He returned the following month with a team of researchers to retrieve samples.)
Toward the end of our last day at sea, Misty turns down the east side of Cortes Island. Stamets spots another agarikon growing 35 feet above the water under the bottom branch of a Douglas fir, sweating beads of amber. He goes ashore for a closer look; while the fungus appears to be dead, he believes the mycelium running up the tree is still alive. Climbing onto an overhanging rock, he finds another one growing in a tree, a sign of an old colony.
Back on deck, Stamets looks across the open water. "How is history going to remember you?" he wonders. "How is Fleming remembered? How are people who have saved millions of lives remembered? I want to die with a smile on my face." He then strips off his clothes and dives into Desolation Sound.