The Patient Forest

I came to the Olympic Peninsula in the autumn of my eightieth year, and I came as an old man comes to one last thing, which is to say with the expectation that it would be ordinary and the private hope that it would not be.

My name is Dr. Elias Penrose. My specialty, for forty-seven years, was plant communication — the study of how flora signal across the root network, across the mycelium, across the thin electrical pathways that bind a forest into something that is not exactly a society but is not exactly not one, either. I was, in my field, reasonably distinguished. I was not, in the world beyond my field, at all distinguished. My life's work had been spent arguing, against substantial scientific resistance, that plants were doing more than we credited them with, and my victories in this argument had been modest. A footnote here. A reluctant concession there. The world, in my field as in all others, did not greatly wish to be told that its assumptions were small.

I had been retired eleven years when the invitation arrived.

It came from a forester named Alina Kostas, whom I had never met, but whose recent publications I had read with the guarded interest one feels for the work of a promising student who is on the edge of either genius or confusion. She was thirty-eight years old, a Greek-American born in Tacoma, and she had spent the last decade monitoring the mycelial activity of the Pacific Northwest old-growth stands. Her letter to me was brief. She had, she wrote, observed a pattern. She did not wish to describe it in writing. She believed I, of all the people still alive, would be best positioned to confirm or dismiss what she suspected.

I went.

The stand was at the edge of the Hoh rainforest — seventeen acres of Sitka spruce and western hemlock, some of them eight hundred years old, their bases draped in club moss that hung in thick green rags and smelled, when you got close to it, like wet earth and old pepper. Alina met me at the trailhead. She was slight, dark-haired, practical. She asked how much I could walk. I told her: enough.

We walked for two hours, to a clearing she had marked with three red ribbons tied to a downed log.

She showed me the instruments. Mycelial electrode arrays buried at depth across a one-hectare grid. Chemical sensors. Sap-flow monitors on twenty-two selected trees. Time-lapse imaging on leaf positions. Eight years of continuous data.

I asked to see the raw feed.

She set up the display on a portable screen.

I watched.

It is difficult, now, to describe what I saw, because what I saw was not obvious. It was not sudden. It was not a signal. It was a pattern of patterns — the subtle difference between a forest whose chemistry reflects environmental response, and a forest whose chemistry reflects environmental response plus something else. The something else was very small. It was well below the noise threshold. It was visible only in the fourth-order derivatives of the electrochemical signals across the mycelium, which is to say it was visible only if you knew exactly how to look.

What I saw, over a period of approximately forty minutes of careful observation, was a pattern of pulses that did not correspond to any known biological process. The pulses were brief. They propagated across the grid in a spiral. They repeated, with variations, every forty-seven hours.

I sat down on the downed log.

Alina watched me.

"How long," I asked, "have they been doing this?"

"Based on the archival data from my colleagues," she said, "no less than sixty years. Possibly more. We were not looking for it, so we did not see it. Once I isolated the signature, I back-propagated through the public datasets. It was always there. We were always missing it."

"It" — we both knew, without saying it, what the word referred to.

The debate, of course, had been going on for a century.

In 1966, Cleve Backster attached galvanic skin response sensors to a dracaena plant and claimed it responded to his thoughts. He was ridiculed. In 2006, Peter Wohlleben argued in his popular writings that trees communicated across root systems in ways that amounted to rudimentary cooperation. He was read widely and scientifically marginalized. In my own early career, I had published a paper arguing that the electrical signaling I was measuring in Douglas fir was sufficiently complex that one could reasonably describe it as information exchange. My tenure committee had asked me not to use the word "information."

And here, now, on a downed log in an old-growth forest at the end of the world, I was looking at data that demonstrated not merely information exchange but what appeared to be structured, repeated, purposeful communication. Something was being said. For sixty years. Possibly for much longer. By a forest.

"Have you told anyone?" I asked.

"I have told you."

"What do you intend to do?"

"That," Alina said, "is why I asked you to come."

We sat in the clearing for a long time. The club moss moved in the breeze. A raven called somewhere deeper in the stand. I thought about the years I had spent arguing for small concessions. I thought about the tenure committee. I thought about the scientific press. I thought about what would happen if Alina published — about the mockery, the demands for replication, the accusations of sloppiness, the quiet pressure on her young career. I thought about how easy it would be for the conversation we were now having to be buried under the weight of institutional inertia for another sixty years.

Then I thought about something else, which was this: if the forest had been communicating for sixty or more years, and we had not noticed, then the forest had not been communicating with us. It had been communicating with itself. We were, to the forest, what a deaf stranger at a dinner party would be — perhaps pitied, perhaps ignored, but not addressed.

The question, then, was not whether we should listen.

The question was whether, having finally begun to hear, we would have the courtesy to announce ourselves.

I am writing this from my study in Seattle, where I have returned to settle certain affairs before going back to the Olympic Peninsula to continue working with Alina. We have agreed to publish. We have also agreed to do something which has, to my knowledge, never been done in the history of botanical research. We are designing an outbound signal.

It will be electrochemical. It will propagate across the mycelium. It will contain, in its simplest elements, a single repeating proposition, encoded in the cadence of the forest's own signaling: you are not alone on this hillside.

Whether they will understand us, we do not know.

Whether they will answer, we do not know.

Whether they have, in all these quiet centuries, been speaking about anything that would interest us — or whether we are, to them, merely the noise that passes through the wind, the rain, the brief and disordered creatures whose roots do not touch — we do not know.

But I am an old man, and I have spent my life insisting that plants were thinking something, and now that it turns out I was correct, the only thing left to do, the only thing I can do with whatever time I have, is to introduce myself.

The patient forest has been waiting.

It is time we said hello.