This topic of trees communicating and living a communal life has suddenly become popular over the past few years. Although scientific studies and papers have been around for a while, the general population was introduced to the concept a few years back with the book, “The Hidden Life of Trees,” authored by Peter Wohlleben. (I highly recommend it.) The science has been advanced subsequently by more books that “teach” us about the concepts, and also been found its way into fiction. The best and most popular example of fiction writing with the concepts that comes to mind is “The Overstory,” authored by Richard Powers, for which he was awarded last year the Pulitzer for fiction.
One thing I leared from Peter Wohlleben’s book is that trees, at their crown height, tend not to get all tangled up. Next time you’re in a forest, look up and confirm that. I now see that all the time. For example, our yard. We have lots of very tall, very old swamp (white) oaks and a few bur and red oaks in our yard and on the adjacent parkway. The other evening, as I was with the dogs in the back doing their go-pee-before-bed routine, I noticed that the “younger” or smaller swamp oak next to our deck really has no crown on its south end. Why? Because two other much older and larger swamp oaks are to the immediate south and have crowns that are large and approach the younger guy and “invade” its space. Their communication to each other tells the younger guy to behave, be subservient and leave the crown space alone for the old guys. Here’s a photo that I took today showing how the young one (on the left) defers to the two elders (on the right):
Excerpt from this
New York Times story. The story is long, so the excerpt is just a small piece of the story. It’s worth a click into the link (and hopefully you won’t run into a paywall).
Underground, trees and fungi form partnerships known as mycorrhizas: Threadlike fungi envelop and fuse with tree roots, helping them extract water and nutrients like phosphorus and nitrogen in exchange for some of the carbon-rich sugars the trees make through photosynthesis. Research had demonstrated that mycorrhizas also connected plants to one another and that these associations might be ecologically important, but most scientists had studied them in greenhouses and laboratories, not in the wild. For her doctoral thesis, [Suzanne] Simard decided to investigate fungal links between Douglas fir and paper birch in the forests of British Columbia. Apart from her supervisor, she didn’t receive much encouragement from her mostly male peers. “The old foresters were like, Why don’t you just study growth and yield?” Simard told me. “I was more interested in how these plants interact. They thought it was all very girlie.”
Now a professor of forest ecology at the University of British Columbia, Simard, who is 60, has studied webs of root and fungi in the Arctic, temperate and coastal forests of North America for nearly three decades. Her initial inklings about the importance of mycorrhizal networks were prescient, inspiring whole new lines of research that ultimately overturned longstanding misconceptions about forest ecosystems. By analyzing the DNA in root tips and tracing the movement of molecules through underground conduits, Simard has discovered that fungal threads link nearly every tree in a forest — even trees of different species. Carbon, water, nutrients, alarm signals and hormones can pass from tree to tree through these subterranean circuits. Resources tend to flow from the oldest and biggest trees to the youngest and smallest. Chemical alarm signals generated by one tree prepare nearby trees for danger. Seedlings severed from the forest’s underground lifelines are much more likely to die than their networked counterparts. And if a tree is on the brink of death, it sometimes bequeaths a substantial share of its carbon to its neighbors.
Although Simard’s peers were skeptical and sometimes even disparaging of her early work, they now generally regard her as one of the most rigorous and innovative scientists studying plant communication and behavior. David Janos, co-editor of the scientific journal Mycorrhiza, characterized her published research as “sophisticated, imaginative, cutting-edge.” Jason Hoeksema, a University of Mississippi biology professor who has studied mycorrhizal networks, agreed: “I think she has really pushed the field forward.” Some of Simard’s studies now feature in textbooks and are widely taught in graduate-level classes on forestry and ecology. She was also a key inspiration for a central character in Richard Powers’s 2019 Pulitzer Prize-winning novel, “The Overstory”: the visionary botanist Patricia Westerford. In May, Knopf will publish Simard’s own book, “Finding the Mother Tree,” a vivid and compelling memoir of her lifelong quest to prove that “the forest was more than just a collection of trees.”
Before Simard and other ecologists revealed the extent and significance of mycorrhizal networks, foresters typically regarded trees as solitary individuals that competed for space and resources and were otherwise indifferent to one another. Simard and her peers have demonstrated that this framework is far too simplistic. An old-growth forest is neither an assemblage of stoic organisms tolerating one another’s presence nor a merciless battle royale: It’s a vast, ancient and intricate society. There is conflict in a forest, but there is also negotiation, reciprocity and perhaps even selflessness. The trees, understory plants, fungi and microbes in a forest are so thoroughly connected, communicative and codependent that some scientists have described them as superorganisms. Recent research suggests that mycorrhizal networks also perfuse prairies, grasslands, chaparral and Arctic tundra — essentially everywhere there is life on land. Together, these symbiotic partners knit Earth’s soils into nearly contiguous living networks of unfathomable scale and complexity. “I was taught that you have a tree, and it’s out there to find its own way,” Simard told me. “It’s not how a forest works, though.”
After a few hours of digging up roots and collecting samples, we began to hike back down the valley. In the distance, the granite peaks of the Selkirks bristled with clusters of conifers. A breeze flung the scent of pine toward us. To our right, a furtive squirrel buried something in the dirt and dashed off. Like a seed waiting for the right conditions, a passage from “The Overstory” suddenly sprouted in my consciousness: “There are no individuals. There aren’t even separate species. Everything in the forest is the forest.”
