There are only a few scientists who have in recent decades changed the way we view the natural world. Perhaps not coincidentally, most of them are women.
One thinks of Jane Goodall, whose landmark study of chimpanzees in Tanzania’s Gombe Stream National Park demonstrated that chimps possess distinctive personalities and rich emotional lives, and form hierarchical societies not unlike our own. Marine biologist Rachel Carson sounded the alarm about the dangers posed by the pesticide DDT and other synthetic chemicals to the fragile web of life on Earth. And microbiologist Lynn Margulis helped develop the Gaia hypothesis, which posits that the Earth can be viewed as a single self-regulating organism. The planet is a complex entity whose living and inorganic elements are interdependent, and whose life-forms actively modify the environment to maintain the most hospitable conditions for flourishing.
Suzanne Simard is another researcher in this paradigm-bending mold. What Simard shares with her pioneering sister scientists is the conviction that humans are not separate from nature, but integral participants in life’s unfolding drama. This is the perspective she shares in her new book, “When the Forest Breathes: Renewal and Resilience in the Natural World,” which combines personal memoir with descriptions of her scientific investigations.
Why We Wrote This
Growing up in a family of loggers, Suzanne Simard always loved forests. Her boundary-pushing research reveals other, deeper layers to the forest ecosystem.
We learn about Simard’s struggles with her health and with grief, and how these experiences resonated with her growing awareness of the natural cycles within the forest.
“I wanted to learn what the mother trees could teach me about survival and adaptability, about life and death,” she writes.
Simard was born into a family of loggers and grew up in a rare inland rainforest near the city of Nelson, in British Columbia. She went on to study forest ecology at the University of British Columbia, where she engaged in the fieldwork that became the basis of the bestselling “Finding the Mother Tree: Discovering the Wisdom of the Forest.” In the book, she makes the case that trees routinely communicate with one another, share carbon and other resources through mycorrhizal networks underground, and forge cooperative relationships among themselves and with other species in their immediate environment.
It was that rare science book that fired the public imagination, becoming the model for Richard Powers’ bestselling novel “The Overstory,” as well as a Hollywood film about Simard’s life, which is still in production.
Bill Heath from When the Forest Breathes © 2026 By Suzanne Simard. Excerpted by permission of Alfred A. Knopf, A Division of Random House LLC
In “Finding the Mother Tree,” Simard challenges the idea of survival of the fittest, which holds that every living organism is locked in a fight to the death for limited resources with every other organism. Though Simard acknowledges that competition plays an important role in the regulation of life, so, too, does cooperation, she asserts. The forest thrives when competition and cooperation are in balance.
“One of my key findings,” Simard writes, “is that the biggest, oldest trees – the mother trees – are the energetic keystones of the forest.” These trees sequester more than half the carbon in the forest, helping to slow the progression of climate change. They also serve as the hub of fungal networks.
These dynamic mycorrhizal networks have been dubbed the “wood wide web” by the science journal Nature, in an article about Simard’s findings. But Simard does not take personal credit for its discovery. She contends that Indigenous people have long understood the intricate interconnections with the forest. The ancient worldviews of people such as the Kwiakah, Ma’amtagila, and Haida in British Columbia are offering us a new way of understanding life, Simard says, which is really a very old way: the appreciation of the radical interdependence of everything in nature.
While Simard’s ideas have received a generally enthusiastic reception from the public, they have received mixed reviews from her fellow scientists, some of whom accuse her of anthropomorphizing trees – investing them with intelligence and agency. Simard replies that the data she and others have collected over the past few decades speaks for itself.
But she isn’t content with showing us that trees are more remarkable than we’ve given them credit for. Simard wants readers to be inspired by her findings to save them. Much of the book is an impassioned argument for preserving forests and helping them to regenerate.
In a time of global warming and large-scale extinction, humans can no longer simply do science for science’s sake. Simard says we need to use our knowledge of nature’s own cycles of renewal to repair damaged ecosystems and help forests to cope with a changing climate. She says it is critical that we develop science-based alternatives to the clear-cut logging that has felled more than 97% of British Columbia’s old-growth forests.
Data shows that it will take centuries for clear-cut forests in Canada and elsewhere to recover, if indeed they ever do. The heavy machinery employed by loggers compacts the soil and destroys the understory species that are vital for the health of the forest. Such logging leaves little behind to “bootstrap the ecosystem back to health.”
Clear-cuts open the land to flooding and erosion. They also leave remaining forests at increased risk for wildfires. Where forests are cut down, rainfall driven by the transpiration from trees decreases. The climate becomes hotter and drier. Lush ecosystems can turn to virtual deserts overnight. The biodiversity that keeps the forest healthy is critically reduced.
Simard writes that, in 2001, as a result of human disturbance, the forests of Canada “shifted from being net sinks of greenhouse gases [which absorb and hold carbon] to net sources.” Such gases are generated by decomposing organic matter and the burning of slash left by loggers.
In an effort to explore alternative logging methods that help to preserve forests, The Mother Tree Project was launched in 2015 by Simard and other scientists at the University of British Columbia.
Her message then, as now: We need to preserve our forests, not just for the forest’s sake, but for our own.
“When the forest breathes out, we breathe in,” Simard writes. “When the forest thrives, we thrive. When the forest lives, we live.”
