The Treeline: The Last Forest and the Future of Life on Earth
by Ben Rawlence
St. Martin’s Press, 2022
The treeline is the line between climates temperate enough for woodland, and the bordering tundra, desert, or mountains where the wind does not allow tall growth.
The Arctic treeline is the so-called boreal forest of spruce and pine, birch, and larch, and it lies in a semi-circle 50 to 60 degrees north latitude where July temperatures average ten degrees Celsius. Not a place for sunbathing. The boreal is what Ben Rawlence calls “the lung of the world.” Spanning the political borders of Scotland, Scandinavia, Siberia, Greenland, Alaska, and Canada, this forest grows a third of all the earth’s trees and covers twenty percent of the earth’s landmass.
It is not stable. In fact, according to Rawlence, the “trees are on the march.” Responding to a warmer climate they are moving north. While more trees are good for the planet, adding to its oxygen, and sucking up its carbon dioxide, those that are invading the tundra melt the permafrost, exposing bogs of peat and accelerating the decomposition of ancient plant life formerly frozen. Such rotting sends more carbon dioxide and methane into the air. Some scientists believe this ratio of gases will suddenly tip catastrophically and cause huge loss of animal, bird, and human life.
Ben Rawlence traveled to the northern reaches of the world to interview people who live on the front lines of this climate change. His report is alarming. Ice is cracking, and snow no longer blankets the reindeer territory in Finland, confusing the animals.
As Rawlence points out, trees have always offered medicine to traditional peoples. Pharmaceutical companies have not been slow to isolate the compounds trees exude and manufacture them commercially. But what if the trees all disappear and medicines we have not yet even discovered disappear forever?
If you’ve ever walked in the forest you’ll notice how fresh the air is, and how it inspires you to breathe deeply and relax. We, as a species, are meant to do this – to live with trees. The balsam poplar of the Canadian boreal forest is a keystone species and delivers medicine to the air we breathe. In spring the tree’s resin, which has held its buds in a secure grip, melts, releasing aerosols into the atmosphere. These aerosols, it has been discovered, delivers anti-inflammatory, anti-bacterial, and anti-fungal molecules as well as prostaglandins and oxytocins. These chemicals are essential to humans.
This beautifully written, thoughtful, and well-researched book poses the problem of climate change in dramatic terms. Climate change has always happened on earth, and species adapt. But evolution is slow and adaptation may take thousands, or hundreds of thousands of years to work successfully. In the meantime, millions of plants, insects, animals, birds, and humans will die early. Can we not use that human ingenuity that has made us the earth’s most “successful” animal to find a way to halt the world’s warming fast enough to allow our precious biodiversity to adapt?
Of all the books and articles on climate change I have read recently, this book was the most arresting. Ben Rawlence is to be congratulated for this piece of research and for making it so accessible to the layperson.