The makers of a mycelium-based packing material want to make plastics obsolete.Photograph by Bartholomew Cooke

Gavin McIntyre, the co-inventor of a process that grows all-natural substitutes for plastic from the tissue of mushrooms, holds a pen or pencil in an unusual way. Gripping it between two fingers of his right hand, he moves his arm across the paper so that his wrist grazes the inscribed line; because of this, he uses pens with ink that doesn’t smear. When he draws an explanatory diagram of the chitin molecule—chitin is the principal component of mycelium, the white, rootlike vegetative structure of fungi—he bends over his work, then looks up earnestly to see if his hearer has understood. The gesture makes him appear younger than his age, which is twenty-eight. He wears glasses and has straight black hair, dark eyes, and several piercings, with studs in his lip and ears.

The other co-inventor, Eben Bayer, won’t be twenty-eight until June. Bayer is almost six-five, and often assumes the benign expression of a large and friendly older brother. His hair is brown, short, and spiky, his face is long, and his self-effacing manner hides the grand ambitions that people who come from small towns (Bayer grew up in South Royalton, in central Vermont) sometimes have. When he says, of the company that he and McIntyre founded, “We want to be the Dow or DuPont of this century,” he is serious. He is their company’s C.E.O., McIntyre its Chief Scientist. People with money and influence have bet that they will succeed.

Not long ago, McIntyre and Bayer and I sat and talked in the conference room of their thirty-two-thousand-square-foot factory, in Green Island, New York. They have been friends ever since they met in a design class at Rensselaer Polytechnic Institute, in nearby Troy, during the fall semester of their sophomore year, almost nine years ago. During our conversation, they leaned back and forth and sideways in the room’s flexible ergonomic chairs, meanwhile tapping their iPhones to send and receive texts and e-mails to and from many people, perhaps including each other. McIntyre was wearing running shoes, jeans, a plaid shirt, and a forest-green pullover, and Bayer approximately the same. As they talked about their invention, they mentioned Burt Swersey, the teacher at R.P.I. who became their mentor and adviser.

I said that when I had talked to Swersey a few days before, I had told him of an invention of my own—a device to remove plastic bags from trees, which my friend Tim McClelland and I patented in 1996. Swersey had reacted to my small boast with scorn, saying, in so many words, that it was ridiculous to focus on annoyances like plastic bags in trees when humanity had far worse problems. McIntyre and Bayer both laughed. “Burt was always telling me my inventions sucked!” Bayer said. “And when I came up with an invention he liked he would only ask how I was going to make it better. If I came in with a cure for cancer, Burt would’ve said, ‘O.K., but what about H.I.V.?’ ”

A real, serious problem that humanity has right now is Styrofoam. If the name is used accurately, it applies only to the foamed, extruded polystyrene product patented by Dow Chemical in 1944. Dow’s Styrofoam is blue and serves mainly as a building insulation. More commonly, however, Styrofoam is the name people give to the white foamed polystyrene from which packing peanuts and coffee cups and fast-food clamshells are made. In widespread commercial use since the nineteen-fifties, Styrofoam is now everywhere. After Hurricane Sandy, its clumps and crumbs covered beaches along the Atlantic Coast like drifts of dirty snow.

Pieces of Styrofoam swirl in the trash gyre in the Pacific Ocean and litter the world’s highways and accumulate in the digestive systems of animals and take up space in waste dumps; to reduce New York City’s landfills, Mayor Bloomberg recently proposed a ban on the commercial use of Styrofoam containers. Foamed polystyrene breaks down extremely slowly, in timespans no one is sure of, and a major chemical it breaks down to is styrene, listed as a carcinogen in the 2011 toxicology report issued by the National Institutes of Health.

The Dow chemist who invented Styrofoam, O. Ray McIntire, made it by accident while looking for a substitute for rubber insulation. Many plastics were invented to imitate natural substances, like rubber, wood, bone, silk, hemp, or ivory.

Bayer and McIntyre’s invention, in postmodern fashion, creates natural substances that imitate plastics. The packing material made by their factory takes a substrate of agricultural waste, like chopped-up cornstalks and husks; steam-pasteurizes it; adds trace nutrients and a small amount of water; injects the mixture with pellets of mycelium; puts it in a mold shaped like a piece of packing that protects a product during shipping; and sets the mold on a rack in the dark. Four days later, the mycelium has grown throughout the substrate into the shape of the mold, producing a material almost indistinguishable from Styrofoam in form, function, and cost. An application of heat kills the mycelium and stops the growth. When broken up and thrown into a compost pile, the packing material biodegrades in about a month.

The name of the company is Ecovative Design, L.L.C. “Ecovative” is pronounced with the accent on the first syllable, like “innovative,” and the first “e” is long. I found it hard to get the hang of pronouncing the name, and for a while I thought that Bayer and McIntyre should look for a simpler one. But after talking a lot about the company with its principals and employees, almost all of whom are under thirty, I got to like “Ecovative” because of the way they said it. The people who work for the company are devotees of it, and of larger causes. Some employees took vacation days to participate in Occupy Wall Street; two of them were arrested there.

Referring to their product, the Ecovative people sometimes use the phrase “disruptive technology.” Founded six years ago, the company has doubled in size every year, and now employs about sixty people at the Green Island factory. Last June, Ecovative licensed its process for making mycelium-based packing material to Sealed Air, a $7.6-billion international packaging company best known for Bubble Wrap. Sealed Air is building a factory to manufacture Ecovative packaging products in the Midwest. The products can be made almost anywhere, with local agricultural wastes and minimal use of energy. Ecovative’s eventual goal is to displace plastics all over the world.

Kathleen and Gary (Mac) McIntyre, Gavin’s parents, have spent most of their careers working for Brookhaven National Laboratory, on Long Island. Mac is a mechanical engineer who designs and sometimes also makes parts for Brookhaven’s heavy-ion collider and other experimental apparatus. Kathleen, whose degrees are in radiation science and biology, has held a variety of jobs at the laboratory. She is now the operations manager for its Radiological Assistance Program. Gavin was a good student and an Eagle Scout, and he picked up a wide knowledge of science and engineering from his parents. Starting in high school, he did intern jobs at Brookhaven. By the time he was twenty, he was working on accelerator optics, helping to design programs for the focussing and steering of particle beams.

Gavin went to Longwood High School, near Yaphank, Long Island, which has almost three thousand students, and seven hundred or more in a graduating class. Eben, in rural Vermont, attended school in a modest-sized one-story building where the kindergarten was at one end and the high-school classrooms at the other. Eben’s mother, Robin Dutcher, is a writer and publicist. From 1997 to 2003 she was the editor of Steerforth Press, a publishing house in South Royalton. His father, Todd Bayer, was a maple-sugar farmer with a hundred-and-forty-five-acre sugar bush. After Eben’s parents divorced, when he was ten, he divided his time between the maple-sugar farm and his mother’s apartment in town.

Todd Bayer is now seventy-eight, with the upright frame of a young man and a full white mustache and head of hair. He still lives on the farm, though he no longer makes syrup commercially. Eben was a strong kid who could do heavy farm work with his dad—haying, logging, splitting firewood, and constructing a sugarhouse out of salvaged parts and recycled metal. To boil the sap, Todd enlisted his help in assembling a complicated wood-chip gasification burner that attained temperatures of two thousand degrees and required care so that the smokestack wouldn’t set the roof on fire.

Ranks of maple trees rise on the rocky hillsides above the farm. In early spring, Todd and Eben would tap several thousand of the best trees and connect them to a vat in the sugarhouse by PVC tubes in a far-flung network along the steep ground. “It’s quite a job to get over the sugar bush on snowshoes twice a day, checking for leaks,” Todd told me when I visited. “No one was faster or better at that than Eben.” Another of Eben’s chores was to move the wood chips to the burner from an open bunker made of telephone-pole sections and chicken wire. Though covered with a tarp, the pile of chips sometimes got wet and sprouted mushrooms. Eben noticed how the fine white fabric of their mycelium sometimes grew through the pile so tenaciously that big bunches of chips stuck together in a single clump when he lifted them with a pitchfork.

Burt Swersey’s grandfather Loeb Rosen died in the Triangle Shirtwaist Fire, in lower Manhattan, on March 25, 1911. The story of that disaster remained current in the family. After getting a degree in mechanical engineering from Cornell, in 1959, Swersey invented a super-accurate scale to monitor the progress of burn victims. He made other inventions in the medical field, created and sold several medical-equipment companies, and in his fifties moved on to other enterprises (farming, running a plant nursery). He is seventy-six years old and has been teaching at R.P.I. for twenty-three years. Swersey’s face is particularly well adapted to register “Eureka!” moments: his dark eyebrows shoot up, his eyelids widen in delight, and the many worry lines around his eyes smooth out.

One of the classes that Swersey teaches is called Inventor’s Studio. In it he leads students toward making inventions and, eventually, building companies with them. When Eben and Gavin took the class in the fall term of their senior year, neither came up with anything very workable at first. Gavin’s idea for a car-exhaust attachment that would burn off emissions with charged plasma was ingenious but probably unsafe. (“Basically, you’d be driving around with a lightning bolt in your tailpipe,” Gavin says.) Eben’s idea for a no-moving-parts turbine that could generate electricity in high winds by means of sound did not impress Swersey at all. “He was coming up with cockamamie wind generators that would only work in hurricanes, different ways of saving energy with window sealant—just nonsense,” Swersey said.

Toward the end of the semester, Eben thought of a previous R.P.I. class, in which he had been given the problem of making insulation panels out of a mineral called perlite. The difficulty with perlite is that it’s loose, like handfuls of popped popcorn, and tends to settle. Remembering what the mycelium had done in the wood-chip pile, Eben had ordered a grow-it-yourself mushroom kit while he was home during a break. He took the mushroom spores the kit contained, combined them with water and nutrients in a glass jar, added some perlite, and put the jar in the basement. When he checked a few days later, the jar held a solid white disk of perlite knit together by mycelium strands.

With not much else to show for the semester of Inventor’s Studio, Eben brought the perlite disk to class. “He takes this thing out of his pocket,” Swersey recalled, “and it’s white, this amazing piece of insulation that had been grown, without hydrocarbons, with almost no energy used. The stuff could be made with almost any waste materials—rice husks, cotton wastes, stuff farmers throw away, stuff they have no market for—and it wouldn’t take away from anybody’s food supply, and it could be made anywhere from local materials, so you could cut down on transportation costs. And it would be completely biodegradable! What more could you want?”

Swersey knew that Eben and Gavin had been talking about starting a company. He told them to take his course again the following semester. They wouldn’t have to come to class, just work on this invention and on starting a business around it. He would oversee, and put them in touch with a patent attorney. At the end of that school year, during a reception for the new graduates of the School of Engineering, Swersey gathered Eben and Gavin and their parents and hugged them all together and said, “We have to support these kids.”

In the Ecovative conference room, Eben was leaning in one direction in his flexible ergonomic chair and Gavin in another, each meanwhile looking at his iPhone out of the corner of his eye. I asked what they had done after graduation.

Eben said, “I went home to Vermont. But Burt kept calling me, saying I had to come back and work on our invention, because it couldn’t wait. He said we had to jump with both feet. I forget how many times he called. One time, I was out in the yard with my girlfriend and I wanted to throw the phone.”

Gavin: “We were thinking we would start the jobs we’d been offered and work on the invention in our spare time. But Burt said that wouldn’t be enough.”

(Swersey: “I told them I would take money out of my I.R.A. and invest it with them if they would come back to Troy and use the start-up facilities at R.P.I., and devote themselves to their invention and their business full time. Also, that summer they won a fifteen-thousand-dollar grant from the National Collegiate Inventors and Innovators Alliance, which I’m a member of. Now they couldn’t refuse.”)

Eben: “So Burt persuaded us. I had a defense-industry job, at Applied Research Associates, in Vermont, and I went in on my first day and said I wasn’t going to be taking it, and Gavin turned down his job at Brookhaven. We moved back and got an apartment in Troy. We figured we had about three months of money.”

Gavin: “R.P.I. gave us free space on the ground floor of a building they called the Incubator, which was for students and recent graduates starting businesses. At first, we had no idea what we were doing.”

Eben: “We were experimenting with all kinds of materials to use for the substrates. We set stuff on fire—”

Gavin: “I wanted to sterilize a fifty-five-gallon steel drum so we could keep some materials in it. I poured some isopropyl alcohol all around on the surface of the inside and tossed in a match, and nothing happened, so I looked in, and—poof! The flame took off my eyebrows and scorched the front part of my hair to ash. I thought I might have a burn, but I sat for a while with a bag of frozen peas on my forehead and I was O.K.”

Eben: “We tried all kinds of substrates—lint from a clothes dryer, Jell-O, lobster shells (those smelled so disgusting our interns made us promise never to do it again), even hair that we got from Sam Harrington, the first R.P.I. graduate we hired. He had long hair then. If it worked, we were going to call the product Hairsulate.”

Gavin: “It was an iterative process, very Edisonian.”

Eben: “We used a drying oven with aluminum flashing and it caught fire all the time and set off the fire alarms.”

Gavin: “The first time or two, we said, ‘Sorry—we were microwaving some popcorn.’ But there were some awful smells. People caught on.”

Eben: “The Fire Department was coming about twice a month. Everybody in the building would have to troop down to the parking lot, and we became kind of unpopular. But, you know, a lot of the other businesses in the Incubator were Internet start-ups.”

I pointed out that he seemed to say “Internet start-ups” with disdain.

“All you need to be an Internet start-up is a desk, an Internet connection, a couple of beanbag chairs, and some cases of Red Bull,” Gavin said.

“Internet start-ups are great,” Eben said. “But they’re not, you know—making anything.”

Herbert Henry Dow, the founder of the Dow Chemical Company, went to the Case School of Applied Science (now part of Case Western Reserve University), in Cleveland, Ohio, and started his first chemical company in 1889, when he was twenty-three. Dow was fascinated with brine, and with the vast sea of it that underlies Ohio and Michigan. His first patent was for a means of extracting bromine from brine. Dow Chemical, which he founded in 1897, at first sold mainly bromine, bleach, and other chemical substances derived from brine.

According to “Growth Company: Dow Chemical’s First Century,” by E. N. Brandt, the company got into plastics in the nineteen-thirties. Willard Dow, who took over when his father died, wanted his chemists to come up with new uses for ethylene, a gas with many applications, which Dow was producing in abundance at a new factory. Robert R. Dreisbach, “one of the most eccentric persons who ever worked for Dow,” proposed combining ethylene with benzene, a liquid obtained from coal tar, to make ethylbenzene. That chemical could then be put through another process to produce a monomer called styrene, from which many plastics could be made. The idea proved feasible, but Willard Dow decided against pursuing it.

The dedication of Robert Dreisbach and other Dow employees who believed in styrene kept that project alive, more or less secretly, despite the company’s determination to cancel it. At a Dow facility in Michigan, there were hundreds of steel drums of styrene sitting in a field and threatening to explode in the sun; they had to be hosed down regularly, and nobody knew what to do with them. Then the Second World War began. The Japanese invaded Southeast Asia, and America lost its main source of natural rubber. The most practical way to make artificial rubber involved combining styrene with butadiene; the need for artificial rubber lifted styrene to the status of a vital war material. Dow was the only American company making it. Production of both chemicals increased gigantically, Dow built styrene plants all over the country and in Canada, and Dreisbach and the other original supporters of styrene at the company were heroes.

Styrene is called a monomer because its molecule is a basic building block from which more complex molecules—polymers—can be made. Polystyrene, a polymer of styrene, is one of the main plastics of the world. Like almost all plastics, polystyrene is a hydrocarbon derived mainly from oil or natural gas. Through reactions induced by combining chemicals under differing conditions of temperature, pressure, and catalysis (high-school chemistry, don’t fail me now), hydrocarbon molecules can be transformed into a great variety of substances that did not exist before. As Ecovative’s boosters point out, plastics manufacturing takes hydrocarbons that the earth required sixty-five million years or more to create, transforms them in an instant or two of chemical reaction, and produces materials that may still be around sixty-five million years from now.

People did not give much thought to that during the war. The war weaponized plastics, in a sense; many of their first uses were military. When O. Ray McIntire foamed polystyrene with a gas under pressure and created a solid—Styrofoam—that was ninety-five-per-cent air, he gave the Navy and the Coast Guard a new flotation material that quickly saw use in boats and life rafts. Other inventors adapted his process to make containers and packaging.

The word “polymer” has its origins in chemistry. It comes from two Greek words, “many” and “part.” A polymer is a compound or a combination of compounds consisting of structural units (molecules of styrene, for example) that repeat. The endless variability of plastic polymers has been a wizard’s wand. They are like infinitely manipulable Legos that can be put together to make almost anything—but then are difficult or impossible to take apart. Herbert Henry Dow based his company and his future on an insight he had as a young man, when he guessed that the bitter taste of brine from an Ohio well indicated bromine. Eben Bayer’s inspiration of the wood-chip pile, the source of future inventions and industry, saw the engineering possibilities of a living polymer, fungal mycelium.

Instead of hunting for venture capital, Eben and Gavin financed their company at first by winning grants and competitions. They were calling the company Greensulate then, because they were concentrating on a promising insulation panel that the National Institute of Standards and Technology, in Gaithersburg, Maryland, had let them test in its labs. Greensulate had performed better than Styrofoam as a fire retardant and only fifteen per cent less efficiently as an insulator. (To compensate, they made the Greensulate panel fifteen per cent thicker.) In November of 2007, they won a five-thousand-dollar engineering competition in Seattle, and in December they came in first in an international competition for environmental entrepreneurship hosted by the business school of Oxford University.

They were still in their ground-floor offices in the Incubator, still proceeding by Edisonian hit-or-miss. The Oxford competition, with a twenty-thousand-five-hundred-dollar first prize, got the attention of the Albany Times Union. Other papers in the region had also noticed them. Sue Van Hook, a senior teaching associate in biology and natural sciences at Skidmore College, in Saratoga Springs, saw one of the articles and called them on the phone.

Van Hook is a tall, slim woman in her fifties, with straight blond hair and eyes as blue as Sinatra’s. She taught at Skidmore for eighteen years. When studying for her degree in botany at Humboldt State University, in California, she took a course in mycology—the study of mushrooms—and was smitten. She wrote her graduate thesis on macrofungi and has been studying mushrooms in the field and under microscopes ever since. “That first phone call, Eben and I talked for two hours,” she told me recently. “I asked if he or Gavin knew anything about fungi, and he said, ‘Not that much.’ I told him that I felt the universe had been directing me to change my life. Skidmore had cut fungi out of the curriculum, and at a Dreaming with the Dead workshop in ’05 I had received a message: ‘Life is mushrooming.’ I was testing him to see how he would react. I told him what had happened the night before—I had seen a milk snake doing a dance of death beside a road near my house, and when I checked again the snake was curled in the shape of a heart. This was a sign that I should do what I loved. Eben listened, and totally got what I was saying. That’s when I knew I could work with him. I asked him, ‘Can we get married?’ ”

Soon after this conversation, Van Hook started as an unpaid mycological consultant with the company. She led mushroom-collecting hikes in nearby forests, giving Gavin and Eben and others an idea of the fungal intelligence running through nature, so the company would be grounded in earth energy and not just in super-fungi that could be used for the product. The Incubator offices were a chaos of airborne spores and dust particles; she taught aseptic techniques to prevent contamination of test samples. In closeup detail, she took everybody through fungal biology. Fungi are plantlike organisms that also resemble animals—they don’t make their own food by photosynthesis, as plants do, but live by digesting organic matter. The mycelium, the basis for all of Ecovative’s manufacturing processes, is the part that does the digesting.

Mycelium consists of threadlike cells called hyphae. These link to each other in various configurations, and the tips of the hyphae liberate enzymes that digest the food sources in the host, which can be dead or living matter. (Certain fungi feed differently, establishing symbiotic relationships with roots of other plants, usually trees.) Mycelium is considered a polymer because of the hyphae, which repeat in the mycelium’s structure just as styrene molecules repeat in polystyrene. Hyphae can be of three kinds—structural, binding, or generative. Ecovative is most interested in the first two. Although hyphae grow from spores, strands of hyphae may be taken from live mycelium, like plant cuttings, and will continue to grow in a new place under proper conditions. Thus Ecovative’s manufacturing processes can occur without the involvement of spores, which is important, because people don’t want to buy products that might contain spores.

Certain mushrooms are better than others for Ecovative’s purposes, and a very few are ideal. Van Hook went on wide-ranging mushroom hunts collecting new species for the company’s archives. At Skidmore’s bio labs, she and her students spent hours cataloguing the finds and recording their characteristics. (Skidmore was as enthusiastic about Eben and Gavin’s invention as R.P.I. had been.) A useful kind of mycelium came from a group of fungi called polypores, which grow mostly on wood. The mycelium of polypores has extra-strong hyphae, as demonstrated by how difficult it is to pull a hard polypore like chicken of the woods off the trunk of a tree. These hyphae can knit a molded piece of substrate solidly together; in general, a single cubic inch of substrate contains eight miles of mycelium.

On her best searches Van Hook began by opening herself to messages she was receiving from her surroundings and letting them lead her, and on one outstanding afternoon in the woods she went from revelation to revelation until she saw before her the polypore that became one of the company’s first workhorses. When she found it, she knelt down and thanked the universe for leading her to it. This polypore is a local conk—a thick, tough kind of polypore—but its name is proprietary information.

At fifty-five, she was able to retire from Skidmore, and she began to work for Ecovative full time as its Chief Mycologist (a salaried position). She sometimes gives lectures about the company; I went to one last February at Cooper Union, in Manhattan. The lecture room was packed. Students and older people, many of them amateur mycologists, filled all the rows and sat in the aisles and stood by the door, where they couldn’t see. On a screen she projected the molecular structures of chlorophyll, starch, glucose, cellulose, lignin, and chitin. She said, “I always tell students of engineering and design that they must understand these molecules. These are the materials that nature builds with. For us to have a sustainable planet, we must design and build with these.”

The world’s biggest competition for CO2-reducing business plans, the Postcode Lottery Green Challenge, takes place each year in Holland. People outside the environmental field may not have heard of it, but the first-prize award—five hundred thousand euros, or about seven hundred thousand dollars—stays in the mind. Finalists make their presentations to an international jury during the PICNIC Festival, a cross-disciplinary conference held in Amsterdam in September. In 2008, after being in business for only about a year, Ecovative sent an entry to the competition, and it made the cut. Eben went to Amsterdam for the presentation, which was to include a speech and PowerPoint display onstage before a thousand attendees. In previous competitions, he and Gavin had always appeared together, but the rules here limited them to a single presenter. Eben had more stage experience, having performed in many plays in high school. He prepared a speech of about ten minutes.

Today, Ecovative often refers those with inquiries about the company to the online video of this speech, along with videos of speeches that both Eben and Gavin have made at TED techno conferences. The speeches serve as founding documents, introductions to the company. Eben’s PICNIC presentation came off with an air of easy authority and persuaded the jury. When Burt Swersey received the phone call telling him that Ecovative had won the five hundred thousand euros, he was teaching a design class. He let out a tremendous yell.

Instead of being sought, venture capital now began to seek Ecovative. Eben and Gavin accepted some investors—the 3M Company, and their alma mater, R.P.I., among them—and rejected others. More grants and prizes arrived; the annual World Economic Forum at Davos invited Eben to attend. From the offices at the Incubator, Ecovative moved to an eight-thousand-square-foot space at the Green Island industrial park. In the PICNIC speech, Eben had talked only about their insulating material, Greensulate, but after production of those large panels had to be delayed they decided to shift emphasis temporarily to their packaging product, because its pieces are smaller and easier to make. Steelcase, Inc., an office-furniture company in Grand Rapids, Michigan, came to them for V-shaped blocks to protect the corners of tables in shipment, and for other buffers and inserts. Dell Computers, Crate & Barrel, and Puma athletic gear made similar requests.

Ecovative still uses its original eight thousand square feet at Green Island, but in 2011 it took over a much larger space, just across the parking lot. The new factory is about the size of a big-box store like a Lowe’s or a Costco. Steel shelves holding sixty thousand in-progress molds filled with substrate and mycelium ascend to the thirty-five-foot-high ceiling. On some days, there is a smell like cream-of-mushroom soup. In a corner of the building, a sealed-off space called the Dirty Room receives the agricultural wastes and other substrate materials when they come in. Big white nylon bags stand there in rows, filled with chopped-up cornstalks and husks, crushed remains of cotton plants after the cotton has been removed, barley hulls, peanut hulls, buckwheat hulls, milo hulls, hemp pith, rice husks, wheat straw, and ground-up old blue denim. The smell of that room leans you back against a hayrick on an autumn afternoon.

Before the substrate materials leave the Dirty Room, they go through the steam pasteurizer, which eliminates contaminants and spores. Presumably, that piece of machinery makes noise. Otherwise, the factory is quiet. Industrial lights hang overhead, casting a purplish tinge. Young people in sweat clothes go here and there, pushing wheeled racks and carrying clipboards.

In the conference room, the messages on Gavin’s and Eben’s iPhones were becoming importunate, sometimes efflorescing into ring tones. The conference table held a wide assortment of products that Ecovative makes, or plans to. The flexible ergonomic chairs pointed their arms here and there as the young inventors showed me stout packaging blocks, pieces of insulation with velvet-soft surfaces, tough flip-flop sandals, and boards as hard as plywood, all grown from mycelium and agricultural waste. “We think we’ve found a pretty good polymer,” Eben said, glancing at his phone.

My father, who was a chemical engineer at a research lab, used to bring home samples of substances never seen before on the planet—strange milky plastics as brittle as ice or as slick and pulpy as squid. Gavin leaned his flexible chair to show me a wonder that reminded me of those. It was a block about the size of half a stick of butter, lighter than balsa, but as hard as pine: a piece of solid mycelium, pure chitin that had been grown from nutrients and without any substrate. He said it had possible applications for aeronautics. I rolled it in my fingers, trying to get a handle on its complete unfamiliarity. He added that chitin is also an excellent insulator, and began to explain how he and his colleagues are growing electric circuits on fungal tissue made of the mycelium of household mold.

In the presence of toxic metals, he said, certain molds get around the toxicity by sequestering the metals onto their cell walls. Therefore you can put tissue taken from the mold into a copper solution, for example, and impregnate the tissue with varying amounts of copper by changing the concentration. In other words, you can make a fungal resistor that can be part of the circuitry in a computer or a cell phone. Then, instead of sending old computers and phones to be taken apart hazardously in the Third World, you can recycle them, with the chitin providing nutrients for new tissue and the metals going back into a solution to be reused.

But now Eben and Gavin’s next meeting had arrived—a delegation of Chinese executives and engineers who wanted to license the process for making mushroom packaging. They were waiting in an observant group near the conference-room door. I shook hands warmly with Eben and Gavin and went out, and the Chinese delegation came in.

Green Island occupies a fortunate place in the landscape. Ever since the channel on its western side was filled in, it’s an island only during extreme high water. On its eastern side, the Hudson River runs just fifty feet behind the high school. The river is tidal all the way from its mouth to here; an incline at Green Island with a cumulative drop of fourteen feet stops the tidal motion from extending farther upstream. When Henry Hudson sailed up the river in 1609, searching for the Northwest Passage, one look at the rapids here told him that this waterway would not be it. A dam has spanned the river from Green Island to Troy since the mid-eighteen-hundreds. In 1922, Henry Ford took advantage of the drop by building a generating station to provide power for a car-parts factory on Green Island. The factory is gone, but the power station is still operating.

The Mohawk River joins the Hudson in numerous branches above the dam, making the Hudson so wide that different parts of it reflect different parts of the sky. Most of the river flows over the dam in a white falls, but about six thousand cubic feet of it goes through the turbines every second. The whole generator building hums, and the flat, whorled water slides out the downstream side like a moving sidewalk. Ecovative likes to say that it gets its electricity only from renewable hydro power. The way power flies around the national grid, that might not always be true; in any case, a lot of Ecovative’s electricity comes from the turbines at Green Island. Most electric power is generated and consumed almost simultaneously. The river with its wide-screen reflection of sky and clouds is keeping Ecovative’s lights on in the moment that it flows past.

Whenever I visit the company, I like to stop first at an abandoned railroad bridge at the north end of Green Island. The branch of the Mohawk that the bridge spans has carved low bluffs from the island’s four-hundred-million-year-old shale. The bluffs resemble stacks of very thin, reddish-black crêpes. All river confluences are glorious. Canoes full of Iroquois Indians travelled past here, and fur traders, and soldiers, and surveyors for the Erie Canal. The canal turned left near this point, followed the Mohawk’s shale valley westward, tapped into the Great Lakes, and made the fortune of New York City. Here, as at all confluences, wildlife congregates. In the early morning, it’s an amphitheatre of birdsong, while Canada geese add their usual commotion. So many crows show up in the evenings that they plague the town of Green Island, and the mayor has to scare them away with a blank pistol.

One Wednesday after a meditation here, I crossed the Hudson to Troy and stopped by Burt Swersey’s Inventor’s Studio class. Rensselaer, the oldest technological research university in the country, overlooks the Hudson from the east. The view from Swersey’s classroom windows, however, was of a roof with some crookneck ventilator ducts that rotated back and forth. On the corkboard were pictures of Eben and Gavin, and news stories about them. They are heroes at R.P.I. The university’s president, Dr. Shirley Ann Jackson, often mentions Eben and Gavin in her speeches. She says that they exemplify the best of R.P.I. and the goal that she champions: “Expedite Serendipity.”

Swersey began the class by having the students tell what they were working on. A young R.O.T.C. cadet who was dressed in camo described his idea for a uniform with built-in tourniquets that would deploy automatically when a soldier was wounded. Other students’ ideas had to do with helping the homeless, asthma sufferers, or people with Alzheimer’s disease. A student from Kuwait suggested a public-area surveillance device that would detect people with incapacitating depression; then professionals could intervene and stop suicides. Swersey listened, offered a mixture of encouragement and skepticism, and told the students to talk to ordinary citizens to get feedback. “Getting out there and talking to people is absolutely critical,” he said. “If you don’t get out and talk to people, your grade is going to suffer.”

Afterward, when most of the students had left, he was franker with the few who hung around to talk. “You’re still not really getting it,” he said, gloomily. “You’re thinking in terms of ideas. I don’t care about ideas. Find a problem, not an idea. Then solve the problem. Somebody had an idea to help stores in India so the food touched by untouchables didn’t have to be thrown away. No—leapfrog that problem! Find the real problem! Forget about the thrown-away food—make it possible for the untouchables to be touchable! It’s all about empathy! Right now you’re attempting small things. I want something fantastic. Not something good, not even something great—something fantastic. Find a problem so outrageous in its scope that it’s probably impossible. Start on it right away—next class. You have only seven more weeks in the semester.”

A young woman named Paula, whose project involved thermo-engineering with plots of solar-heated sand, had been arguing with Swersey, but at this she gave in. “O.K., Burt,” she said. “Before the next class, I will come up with something impossible.” ♦