What do plants and people have in common? More than you think.
“Finding the Mother Tree” and “Lessons From Plants” explore how trees and plants communicate and form interdependent communities.
Knopf/Harvard University Press
Growing up, Suzanne Simard was captivated by the multicolored layers of humus and mineral soils teeming with worms and bugs and nearly impenetrable tangles of roots coiled together with fungus.
How, she wondered, did this exuberant life below the ground connect to the forest above it?
In her book, “Finding the Mother Tree: Discovering the Wisdom of the Forest,” Simard writes about her nearly three decades of work to answer this question. As one of the world’s leading forest scientists, Simard, a professor of forest ecology at the University of British Columbia, would go on to revolutionize the way many researchers think about trees and their relationships with one another.
Simard has become something of a celebrity scientist. She’s said to have been the model for a lead character, Patricia Westerford, in Richard Powers’ 2019 Pulitzer-winning popular novel, “The Overstory.” Her vision of the forest as being innately intelligent inspired filmmaker James Cameron’s 2009 science fiction film “Avatar.”
Still, not everyone is a fan. Some scientists regard her use of words like sentient, maternal, and caring to describe trees as being anthropomorphic. Others say her view of harmony in nature is naive. Commercial lumber interests have chafed at her recommendations to log more selectively.
In part to answer these critics, Simard decided to tell her own story. “Finding the Mother Tree” is a frequently lyrical memoir which puts her work in the context of her lifelong fascination with the forest, and her growing alarm over the massive clearcuts that are transforming the region into a blighted checkerboard.
The author writes rapturously about the beauty of British Columbia, home to one of the world’s last great temperate rainforests, as well as the challenges of working there, which include encounters with grizzly bears, wolves, bugs, and the chemicals that are sprayed by loggers. She also recounts the tragic loss of her brother Kelly, a rodeo artist, her own battle with cancer, and her breakup with her husband when a career move caused the couple to drift apart. This personal narrative reminds us that science is a human enterprise – and, in Simard’s case at least, as much a product of the heart as of the head.
Simard began her career as a forestry researcher investigating why the fir seedlings in a tree plantation were sickly, whereas the young trees in a nearby forest were thriving. The mature trees in the forest, she discovered, were feeding their own young saplings through intricate underground webs of roots entwined with fungus (called mycorrhizal networks). Plantation seedlings, by contrast, had to fend for themselves.
Trees don’t only feed their own young, Simard would go on to find. Many have forged complex trading partnerships with other species as well. For example, birches send sugars to firs during the summer when they are creating more than they need through photosynthesis, and firs return the favor during the fall and spring when the birches lack leaves.
Simard’s field work turned the tables on the view of trees as engaged in a fierce competition with one another for water, mineral nutrients, and access to sunlight. The truth, she found, is closer to the indigenous Salish vision of the forest as “many nations living side by side in peace,” actively working together to support one another and promote the flourishing of the whole.
Moreover, Simard tells us that trees are not just swapping resources, they are also communicating – warning their neighbors in real time about insect attacks and other environmental threats by way of chemical messages sent through the subterranean fungal network, which has been dubbed “the wood-wide web.” The linchpins of this web are the gentle giants that Simard calls “Mother Trees,” which share their carbon bounty and their “wisdom” with those that are less well endowed.
“Plants are attuned to one another’s strengths and weaknesses,” she writes, “elegantly giving and taking to attain exquisite balance.” Simard compares diverse species to “musicians in an orchestra” creating a music together that is greater than the sum of its parts.
It is a breathtaking vision. But are trees really as wise, intentional, and altruistic as the author suggests? Some say the jury is still out. Yet fewer would argue with her contention that we are needlessly destroying these critical ecosystems that hold vast reserves of carbon and that are a bulwark against climate change.
The good news, Simard says, is that forests have an almost miraculous capacity to recover, if humans give them a half a chance. The author’s urgent call at the end of the book to preserve our remaining old-growth forest lands could not be more timely.
‘Lessons From Plants’
Humans have lived on earth for roughly 300,000 years. Plants, by contrast, have been around for a billion years and counting. Beronda L. Montgomery, a biologist who teaches at Michigan State University, argues that plants used that time well, learning how to live in remarkable harmony with one another and with their environment.
Montgomery shares her admiration for these ingenious beings in “Lessons From Plants,” an attractive, pocket-book size hardback illustrated with thumbnail drawings and published by Harvard University Press. Despite the Harvard imprimatur, the book is an accessible and, thankfully, jargon-free introduction to a science that has advanced a great deal recently – and has revolutionized the way that we look at our evolutionary predecessors.
Until recently, biologists thought of plants as essentially passive organisms, responding in genetically predetermined ways to the world around them. They orient their leaves toward the sun, and sink their roots deeper into the soil in search of water during dry times. However, it was assumed that they did so by rote. Plants were seen as being alive (in some vague, preconscious way) but certainly not intelligent or capable of making reasoned decisions.
Far from being unfeeling automatons, however, plants know exactly what’s going on around them, according to Montgomery. Precisely because they are fixed in place and can’t move, they’ve needed to become “nosy neighbors,” continually scanning the environment and reacting swiftly to the changes that they perceive.
We read, for example, that plants modify their own light-gathering proteins in response to the available wavelengths of sunlight, and they angle their stems away from their neighboring kin to avoid mutually destructive competition. Moreover, many species communicate with one another in the language of scent about threats, like invading insect pests. They also share food (especially with their own young) and they form mutually beneficial partnerships with fungi and bacteria, which release essential nutrients from the air and soil in exchange for photosynthesized sugars.
Talents like these lead the author to conclude that plants have a “sense of self” – insofar as they know who they are, where they are, and what they are supposed to be doing.
Does that mean that plants are aware? Wisely, Montgomery does not weigh in on this highly contentious debate. Certainly, plants can’t tell us about their “experience” of the world. But their actions speak for themselves. The author tells us that plants routinely assess risks, make complicated cost-benefit analyses about the use of limited resources, and use them to decide whether to cooperate or compete with neighbors. They also recall the past to help them anticipate future conditions and to plan ahead.
In certain respects, plants are better life-strategists than we are. The author quotes biologist Robin Wall Kimmerer, an enrolled member of the Citizen Potawatomi Nation, as saying that “science asks us to learn about organisms. Traditional knowledge asks us to learn from them.”
Much of the second half of the book draws lessons from plant behavior. Native Americans generally grew squash, corn, and beans (the three sisters) together. Corn provided vertical support for the vine-like bean plants, bacteria in the bean roots fixed nitrogen from the air which fertilized their partners, and the floppy squash leaves shaded the ground, preserving moisture and inhibiting the growth of weeds.
“One of the greatest lessons we can learn from plants is that there is a power in working together,” the author effuses. “We must release our overdependence on individualistic success models....”
Montgomery also applies the lessons she and her colleagues have learned about plants to human relationships. “By studying how plants interact with others, we can see the importance of establishing an ecosystem of support, collegiality, and community,” she writes.
Her attempts to relate her nature studies to academic and business organizational structures can seem at times a bit contrived. She is at her best when she writes more personally, as she does about a white spruce that she planted when her son was born. Watching both boy and tree grow has brought the family joy. She writes of the relationship, “He has been its caretaker, and it has been his teacher for nearly two decades.”
One might have liked more engaging stories like this to add color to the scientific account, which reads at times like a well crafted textbook. But for the curious, “Lessons From Plants” is an excellent introduction to a world that most of us know too little about.