The first day in the forest of British Columbian, when she started her research, Suzanne Simard, a mother grizzly bear and her cub chased her off the job. But she persevered and eventually completed her research. She put on her respirator, and then put plastic bags over her trees to isolate them above ground. With her giant syringes she injected the bags with her tracer isotope carbon dioxide gases. First, she did that to the birch. She injected carbon-14, the radioactive gas, into the bag of birch. And then for fir, she injected the stable isotope carbon-13 carbon dioxide gas. She used two isotopes, because she wanted to know if there was two-way “communication” going on between these species of trees. She wanted to identify the source of the isotopes. She waited an hour because she estimated that this would be enough time for the trees to suck up the CO2 through photosynthesis, turn it into sugars, send it down into their roots. In fact, she hypothesized that the trees would transport the carbon belowground to their neighbors.
When the hour was up, she moved her Geiger counter over the leaves and heard the perfect sound—Kkhh—that indicated to here that in fact the birch had taken up the radioactive gas. Then she moved to the fir tree to see what she would hear there. She heard what to her was a beautiful sound, namely, the same Kkhh! She interpreted this as the sound of the birch tree “talking” to the fir tree. In fact, she interpreted that to mean that the birch was in effect asking the fir tree if it could help it out and the birch “replied” that in fact it could help. Specifically, Simard theorized that the fir was asking for carbon because Simard had placed a shade cloth over it.
This of course is where the sceptic could ask what the justification was for making these conjectures? Was there a better or simpler explanation for the movement of carbon? Was her conclusion a leap of faith instead of an inevitable scientific conclusion based on the available data? I am not so sure, though I find her conjectures deeply intriguing.
After that she examined the cedar and speculated it was silent. The Cedar was in fact in its own world and was not connected to the “Web interlinking birch and fir.” Was there such a web, or was this wishful thinking?
Simard thought the data was clear and irrefutable. In each of her 80 plots she checked all the replicates. The C-13 and C-14 was showing that “paper birch and Douglas fir were in a lively two-way conversation.”
She claimed that the data showed that at that time of the summer, the birch was sending more carbon to the fir tree than the fir tree was sending back to birch and that this was particularly evident when the fir was shaded. At other times of the summer, she discovered that fir was sending more carbon to birch than birch was sending to fir. She speculated that this was as result of the fact that the fir tree was still growing while the birch was leafless. According to Simard, “The two species were interdependent, like yin and yang.”
That led Simard to an epiphany—a Eureka moment. She believed she had made a major discovery that would change forever how scientists look at trees in a forest and how they interact in it. Trees are “not just competitors but…cooperators.” If that is true, that is a revolution in science. She believes that she found solid scientific data that proved there is “a massive belowground communications network, the other world.”
Simard hopes that with new understanding of forests there will come a new way for humans to interact with forest. She really hopes that instead of clear-cutting and instead of applying herbicides we will employ what she called more holistic and sustainable methods. These methods will also be more practical and less costly.
She explained how she viewed her science in relation to these issues. She used science to determine how paper birch and Douglas fir were communicating? According to her research, they were conversing not only in the language of carbon but also nitrogen and phosphorus and water and defense signals and allele chemicals and hormones. All of this she refers to as “information”.
Hard to believe, but…
Maybe forests are more interesting than we ever thought. In fact, maybe nature is ever more interesting than we thought it was.
A story from a professor of Artificial Intelligence. I’ll try to keep the scholarly stink out this note at the risk of saying things in broad strokes. Towards the end of my career, I began to think very differently about intelligence, beginning with definitions of human intelligence with IQ tests (common thought these days), but also recognizing the rather amazing spontaneous actions of other animals. (At the time, most folks studying alternate intelligences looked at apes and their relatives.) As I got interested in gardening, I read that plants have more DNA than we do, perhaps because they have to figure out how to survive when you can’t move, and began to wonder if one could cast what they do as intelligent. Some things can be superficially explained by sensor reactions (following the sun), but there is a lot going on there.
Then I heard about plant signalling – whereby a sick plant can send out signals saying “I am ill, prepare yourself” to other plants that they might do what they could to prepare for the problem. Some see this as just more sophisticated sensor/response action (I say fine to that) but then … is that all we are, albeit in different ways? The new tools – chatGPT, etc. – are impressive when one first experiments with them, and I am often startled more by the side observations they make (as opposed to the solutions they find), but it’s obvious that a computer is the ultimate stimulus-response machine. They even admit it while they are consoling or congratulating you.
My life experience suggests that we (humans) are so much more than that, but one soon becomes mired in where the lines are drawn. Perhaps we are so much more than that – but then so are so many other living things. However, this makes the arguments against the value of IQ tests look almost simplistic.
Bluebirds in Canada have learned a new song, which is spreading. Whales have discovered new ways to collectively fish, the tales about crows and ants are incredible … I’d happily add plants to this community.
The plant world. is always more interesting than one would think. There is a lot of science out there that makes me rethink our relationship to the natural world and also our claims to have the right to dominate it. The case for human supremacy is an uneasy one. It is great to hear from you again.