New book’s globetrotting tour of boreal forests establishes its value to life on Earth

“The Treeline: The Last Forest and the Future of Life on Earth”

By Ben Rawlence. St. Martin’s Press, 2022. 307 pages. $29.99.

The boreal forest, that ring of trees that surrounds the globe at high latitudes, is the largest living system after the ocean; it is also the “lung” of the planet and, therefore, is key to the health of our planet. Ben Rawlence, who lives in Wales and whose latest book is about a refugee camp in Africa, has transferred his concern for human rights to the disastrous effects of climate change. From 2018 to 2021 he traveled the northern forests, to Norway, Russia, Alaska, Canada, and Greenland, to meet residents and scientists and learn for himself what has been happening to northern trees and the life associated with them.

How interesting can the tree line be? Incredibly interesting, it turns out, when the subject is in the hands of such a skillful researcher and writer. We discovered that a book about trees can be a page turner. Part travel adventure, part deep dive into emerging science, part reflection on our history on Earth, part philosophical questioning of Earth’s fate: “The Treeline” is a beautifully written, animated weave of fascinating themes. .

Organizationally, the book goes around the world with each chapter focusing not only on a different forest, but also on the most important tree species for that forest. A map at the beginning, looking down at the North Pole, shows the forests, their northern extent, and the main communities the author visited.

Rawlence begins in neighboring Scotland, considered to be the edge of Europe’s Arctic tree line, though most of its trees were felled centuries ago. Forest succession after the last ice age led to Scots pine once covering about 80% of the land. Today, “renaturation” efforts aim to restore some of that great wood, but global warming projections suggest the UK’s climate will soon be too inhospitable for pines.

In the next chapter, which introduces Norway and European or downy white birch, Rawlence visits Sami reindeer herders in the far north. Here and elsewhere, the author makes it very clear that the health of forests is directly related to human rights and the capacities of indigenous peoples to maintain their cultural ties and livelihoods. Warmer, wetter weather has driven Norway birch to “run” over the tundra, reducing the habitat required by reindeer and their herders.

In the Russia chapter, which features the larch, Rawlence visits various areas of the tree line in the winter and meets with scientists and indigenous people. He travels hundreds of miles in a tank-type vehicle with huge tires to find the world’s northernmost trees: spindly larches that grow in extreme cold conditions on thick permafrost. Elsewhere, thawing permafrost causes water tables to rise and “drowning” larch trees. He learns that scientists predict that at least 50% of Siberia’s forest is expected to become treeless steppe by the end of this century.

When Rawlence researched Alaska’s treeline and dominant spruce species, the world was mired in COVID-19 lockdowns. Unable to visit in person, he did an impressive job studying maps, photos, and reports and speaking with researchers and residents. As he points out, “Alaska is the most studied area of ​​the Arctic; The United States has the resources and the scientific clout that other nations lack…a frontier in our understanding of what is happening both geographically and scientifically.” He details his conversations in Alaska with Ken Tape, who studied how beavers have recently transformed the landscape; writer Seth Kantner, who grew up along the tree line of the Kobuk River; and Roman Dial, who has studied changing vegetative dynamics, especially that of spruce, in the Arctic for more than 40 years. He also details the influences of fungal webs on forest health, how warmer air affects photosynthesis, and the relationship between Alaskan spruce evapotranspiration and rainfall in the American Midwest.

In Canada, Rawlence spent time in Ontario with Diana Beresford-Kroger, “one of the leading scholars of the boreal forest” and, we learn, the model for a character in Richard Powers’ novel “The Overstory,” and later in and around Churchill, on Hudson Bay. Here we learn how critical the northern forest is in regulating water, air, soil, climate, and the productivity of the oceans. We also learn where the book’s subtitle comes from, which refers to “the last forest.” Beresford-Kroger believes the Amazon and other tropical forests are “probably done,” threatened not only by intentional deforestation but also by drought and fires. The boreal forest, being spread over a wide temperature range, may have the best chance to adapt. In Canada, its keystone species is the balsam poplar or poplar.

Rawlence’s last stop, in organization, not in real time, is Greenland. As the island’s ice cap melts, the land becomes more habitable to trees, of which there are four native species, the most significant being the rowan or mountain ash. Rawlence joins a group planting trees and discusses the emerging field of “strategic ecology,” which is based not on current climatic conditions but on guesses about the future. “Assisted migration” is another term related to helping species, including trees, move to places where they could survive in a warmer world.

In the end, by showing how the boreal forest interacts with all life on Earth, Rawlence paints a bleak picture of where we are headed. He does not offer false hope, but instead speaks of a necessary change in the way humans live. Curiosity and observation are the humble but radical requirements for a new relationship with the Earth. Systems change when there is a culture that demands it. The revolution begins with a walk in the woods.” Rawlence’s contributions to the cause include founding and running Black Mountains College, a school in Wales dedicated to teaching skills to mitigate and adapt to climate change.