Richard Preston in his office. (Photo by Suzette J. Lucas.)

Richard Preston demonstrates his spider lanyard tree-climbing technique on a sugar maple near his Hopewell home Dec. 12, 2012. (Photo by Suzette J. Lucas.)

Richard Preston in his office. (Photo by Suzette J. Lucas.)

Richard Preston had a clear view of the ground 300 feet below as he swung suspended from a rope near the top of one of the world’s tallest trees: all around, skeletal eucalyptus rose like skyscrapers from the red earth of Victoria, Australia.

The giant tree he was climbing had looked solid from the ground. It wasn’t until he was almost 30 stories up that Preston found out it was in danger of collapsing at any moment.

Preston was in the midst of researching his nonfiction book, The Wild Trees. For the story, which was published in 2007, he was writing about a community of scientists and thrill seekers who had recently invented methods of scaling the world’s tallest trees and were exploring the mysterious ecosystem of forest canopies.

To write about the tree climbers, Preston, then 49, became one of them, learning their techniques and joining their expeditions. And that was how he found himself, not for the first time in his career, facing the prospect he would never return to Hopewell Township, where he lived with his wife Michelle and their three children.

Like planets, the tallest trees in the world have names. The one Preston was climbing that day was called Nemesis.

He and his climbing partner, Jim Spickler, were nearing the top of Nemesis. Spickler was an experienced climber who has been photographed for the cover of National Geographic twice. They were the second team in recorded history to climb the tree, and they didn’t have much information about it. Spickler had gone first, and Preston followed. It was Preston’s job to measure the tree by pulling a reel of tape along behind him.

Preston eventually caught up to Spickler, finding the climber on a branch curled into a kind of fetal position, his face white as a sheet.

“This tree isn’t stable,” he told Preston.

Spickler had discovered what tree-climbers call a “catface,” an old injury in the trunk of the tree. The bark had stripped away for about 25 feet and the exposed wood had decayed into a substance that has about the same texture and structural integrity as blue cheese. Nemesis had a rotten heart.

That would have been bad news in any tree, but experienced climbers know that in a eucalyptus, it is terrifying.

“Many of these trees have rotten centers and holes right through them,” Preston explained. “They tend to do something called crown detonation. When a rotten eucalyptus tree faces heavy wind, it can undergo a total collapse. The stem of the tree breaks off 50 feet above the ground and the rest of the tree collapses in on itself and it ends up in a huge multiple-ton pile of debris in a ring surrounding this broken-off stump that’s maybe 50 feet tall.”

They were almost to the top of the tree anyway, so they decided to continue. Preston roped his way through the branches, nearing the apex. It was about that time the wind started picking up. The tree began seesawing back and forth in a “C”-shaped pattern.

“It ended up being 50 mph gusts,” Preston said. “You could see it coming: a wall of wind.”

They heard cracking sounds and the tree started vibrating. Spickler told Preston he thought they were going to have a crown detonation while they were aloft. “I went all the way to the top, as far as I could go, and at that point the wind was gusting 50 mph, 30 stories off the ground. I have never been so scared in my life,” he said.

As he swung in the wind, Preston chastised himself for getting into such a situation when he had a wife and kids back home. They got the measurement and rappelled down from the tree as quickly as they could. It was the closest Preston had come to being killed on the job. He didn’t include the story of Nemesis in his book, because he didn’t want to frighten his wife, although he told her about it later.

Nemesis lived for more than a year after that. It burned in the “Black Saturday” brush fires of 2009 that killed 173 people. Preston said eucalyptus trees like Nemesis exploded in the fire because of their flammable sap. He said the forests went off “like nuclear bombs.”

Climbing Nemesis was typical of Preston’s reportorial style. He likes to get to know the subjects of his stories by working alongside them. For his first book, First Light, published in 1987, Preston learned how to help astronomers chart the stars. He joined them in their observatories, working with one team in a modern computerized control room and another that was using an old-fashioned telescope. The second team worked in total darkness in a dome observatory. Preston talked with them in the pitch black, taking notes by feel.

“It turns out that astronomers say the most interesting things in total darkness. They like to work in pitch darkness because they need to get their eyes completely adjusted to low-light conditions,” he said.

Preston rarely records interviews, preferring to scrawl notes and quotes on palm-sized reporter’s notebooks. (He believes people are less likely to talk candidly in the presence of a recorder.) His shorthand is intentionally illegible to anyone but him. The method usually works well, but in the gloom of the observatory, he got his notepad flipped around once, and overwrote over his old notes. There are pages he was never able to decipher.

Despite the lost notes, First Light was a success. Preston won the American Institute of Physics Writing Award for the book, and began a career writing nonfiction for The New Yorker. Preston is best known for a series of three books on the Ebola virus and biological warfare: journalistic works The Hot Zone and The Demon in the Freezer, and the novel, The Cobra Event.

Preston has pewter-colored hair and the ruddy complexion of a man who likes to be outside. His knuckles are scarred from childhood fistfights and his right hand has a chemical burn from an elementary school science experiment. He is outgoing and quick to laugh. When a reporter came by to interview him, he answered the door with Jack, a corgi-Jack Russell terrier mix, at his side.

Preston does most of his writing in an office in a white clapboard farmhouse that doubles as his work area and guest quarters. Sometimes, it is both at once. When Preston wrote The Demon in the Freezer, his editor, Sharon De Lano, stayed for more than a week and forced him to work 18-hour days to perfect the book.

Preston’s office is small but airy. The walls are lined with bookshelves and mementos from his past stories. There is a part from a full-scale wood mockup of the hand-built Hale telescope that Preston wrote about in First Light. There’s a photo of his grandfather Richard McCann, who flew seaplanes in WWI and was one of the Navy’s first 150 aviators. Sitting on a bookshelf, there is an unremarkable-looking fragment of brick that came from the Reston Monkey House, which was the scene of an outbreak of the Ebola virus in 1989.

“I’m convinced that if you take a good whiff of this rock, you can smell monkey urine on it,” Preston said. “But it’s safe.”

Richard and Michelle bought a 75-acre farm near Hopewell Borough in 1998, inking a deal along with their neighbors to preserve both of their farms from future development. The neighboring family grows timothy hay on some of the property. The Preston house is built on the foundation of the old barn. To get to the house, visitors drive up a winding gravel driveway, through a patch of woods, and over a bridge spanning a brook.

The Prestons lived in Princeton before choosing a more rural home.

“My wife and I really love Hopewell. This is by far the best place we have ever lived,” Preston said. “We met as graduate students at Princeton, and for one reason or another we just never left town … Princeton had gotten to be kind of big, and there’s a lot of new wealth. It’s just not the same as it used to be. It doesn’t feel like much of a community. When we came here to Hopewell, we really felt like we were in a community and we really like that a lot. And it’s probably one of the prettiest towns anywhere.”

Preston learned the climbing techniques that took him to the top of the world’s tallest tree, Hyperion, by practicing in Hopewell. The climbing habit followed him back to Hopewell when he finished writing The Wild Trees. Early on, he discovered that even the sugar maples on his own property held little known wonders.

“You find some of the creatures that live up there don’t recognize you as human and aren’t afraid of you,” he said.

One day, four flying squirrels landed on his son when they were climbing together. Another time, he reached out and stroked one of the creatures on the ears.

“It closed its eyes, just like a cat. It stayed that way for awhile, then it woke up and shook itself off, like, ‘What’s happening here?’ and suddenly it took off and soared into the canopy,” he said.

Preston used to climb with his children often, and his middle daughter became the youngest person ever to climb a redwood, at age 16.

Preston went out to a maple in his yard to demonstrate the technique that climbers use to maneuver in the tops of the largest redwoods, via a recently-invented arrangement of ropes, hooks, ascenders and carabiners Preston calls a “spider lanyard.” There are two kinds of rope in Preston’s kit. The first is a 11.5 mm synthetic rope used only for tree climbing. The second is a thinner variety called “tactical rope” of the same type used by commandos to drop from helicopters. A single rope can easily support the weight of a pickup truck. Both run about a dollar a foot.

To the uninitiated, the spider lanyard looks as complex as the rigging on a sailing ship. Four color-coded ropes are hooked via carabiners to a “life ring,” a steel ring that is attached to the climber’s safety belt. To get up the tree, Preston threw a carabiner over a branch, then retrieved it, so the rope was looped around the branch. The main climbing rope is tied in a sliding knot called a “Blake’s hitch” that allows the climber to hoist himself up without sliding back down.

Preston braced himself against the tree with his feet and began to climb. It looked for all the world like he was walking up the trunk. The technique is aptly named “treewalking.”

When he neared the first branch, he hurled a second carabiner over a higher branch, shook the rope to get it back to him, hooked it to his life ring, and then unhooked the first set of carabiners.

It became apparent why the ropes were color coded.

“If you open the carabiners in the wrong sequence, you die,” he said.

By repeating this process, climbers can go to the top of any tree in the world with a relatively small amount of rope, though they usually trail a longer rope behind them in case they need to make a quick exit. To reach the top of a redwood, climbers hoist themselves up with mechanical ascenders until they reach the branches, then use the lanyard method to get around.

Once at the top of the tree, it’s possible to pitch a hammock and spend the night.

As fascinating as Preston finds the world of the canopy and the techniques of tree-climbing, his book is as much about the climbers as it was about the trees. The book is filled with revealing details about the eccentric community of climbers.

And that is true of all of his science writing.

“What I really try to do is tell stories through character,” he said. “I love science. I love the passionate quest of science. But science is a humanistic activity.”

Preston said there is a disconnect between the beautiful, serene and majestic qualities of nature and the terribly human qualities of the people who explore it.

“When I write about astronomers, I can’t fail to point out how they love to eat Oreos,” he said.

Preston takes what he calls “deep notes” when he interviews subjects, asking them to describe their thoughts at key moments.

For The Hot Zone, Preston interviewed Lt. Col. Nancy Jaax, an army researcher who was working with monkeys infected with the Ebola virus. Jaax and the other scientists wore pressurized plastic “spacesuits” to protect themselves against the virus. There is a harrowing scene in the book where Preston describes how the defenses failed, causing Ebola-infected blood to enter her suit. To make matters worse, she had a cut on her hand.

“I conducted a series of interviews with Nancy Jaax,” Preston said. “I sat at her home at her kitchen table, and I asked her to go over with me step-by-step what she was thinking when she was standing in a chemical shower after she had discovered that she had Ebola blood in her space suit. The chemical shower couldn’t possibly reach the Ebola blood that was sloshing around in the spacesuit and maybe into her bloodstream. She had to stand there for seven minutes.

“I asked her what was going through her mind at this moment. Ebola virus, and what it does to people?

“Her answer was really unexpected, and yet perfect: she said, ‘Oh no, I wasn’t thinking about that. I was going, “Aww, s***, I forgot to go to the bank today. The kids are home with a babysitter. Who’s gonna pay the babysitter if I’m in the hospital with Ebola virus? …’” I thought about that, and that is exactly right. She’s a mother and that is exactly what a woman who’s a mother would be thinking in a moment like that … it’s a revelation of reality as Americans really live.”

He also found out the cut on her hand was from opening a can of beans for her kids.

The Hot Zone inspired the Dustin Hoffman movie Outbreak. President Bill Clinton reportedly lost sleep after reading the descriptions of bioterrorism in The Cobra Event.

Preston’s interest in stories about disease goes way back. Preston said that as a child, he faked sick from school to read The Andromeda Strain by Michael Crichton.

Preston was a fan of Crichton’s writing, but never knew him. They did, however share a literary agent, Lynn Nesbit. When Crichton died in 2008, he left behind the unfinished manuscript of a book called Micro. Nesbit asked Preston if he would finish the book for Crichton, and he agreed.

After signing a secrecy agreement, Preston got to look at the manuscript, but was not told the title Crichton had already given it. It was about a third of the way written. Crichton had written the premise: a team of scientists is shrunk down to half an inch tall, and struggle to survive in the wild jungle of Hawaii.

Preston loved it.

“The research in particular excited me because it was about the micro world,” he said.

He wrote a proposal for how he would finish the book, and gave it a title that turned out to be very similar to the real title of the book. Crichton’s widow, Sherri Crichton, decided Preston was the man for the job. Preston flew out to California, where Sherri showed him a photocopy of Crichton’s secret notebooks where he had been jotting ideas.

Preston tried to be as much like Michael Crichton as possible. He watched tapes of Crichton to see how he moved and talked.

“I did a bit of research for it, and I tried to do the research the way Michael would do it. Normally, when I do my research, I like to make contact with scientists to help check my writing and keep me straight. Michael Crichton worked in an entirely different way. He never told anybody what his books were about, so I didn’t have the luxury of going to scientists and have them fact-check what I was writing. That was completely forbidden.”

It being a Crichton book, it’s not giving away too much to say that not all of the scientists make it to the end of the book.

“Michael himself had jotted down a little list of possible ways to die, and I found that very helpful,” Preston said. “I added a few myself. He had written more deaths than there were characters, so he must have intended to cherry pick the deaths. I cherry picked them and made a couple of my own … they had to die and they had to die in Crichtonesque ways.”

One of the deaths was invented by Sherri.

The whole time he was writing the book, Preston had a picture of Crichton’s son, Michael Crichton Jr., on his wall. Crichton died before his son was born, and Preston said he had a sense that he was obliged to finish what Crichton had started.

Micro was published in 2011.

Since then, Preston has been working on an entirely different kind of book.

“I just turned in a manuscript and it’s a children’s book,” he said. “It’s a long chapter book. Think Narnia, or think Harry Potter. It’s about an imaginary world. It’s a story that I’ve had in mind since my kids were little, and I had much earlier versions they used to hear at bedtime.”