THE TREELINE

Trees portend the future of Earth.

A former researcher for Human Rights Watch, Rawlence has reported on vulnerable humans in war-torn Africa and in refugee camps, experiences he potently chronicled in City of Thorns and Radio Congo. His latest investigation focuses on the greatest threat to all life on the planet: climate change. To document global warming, he set out to trace the tree line, the area beyond which trees are not able to grow: “a transition zone between ecosystems” that has moved northward, “no longer a matter of inches per century,” but rather “hundreds of feet every year.” He continues, “the trees are on the move. They shouldn’t be.” The author looks particularly at six trees—three conifers and three broadleaves: Scots pine in Wales; downy birch in Norway; Dahurian larch on the Russian taiga; spruce in Alaska; balsam poplar in Canada; and mountain ash in Greenland. Each reveals a teeming “mosaic of species” as well as indelible practical, cultural, and spiritual contributions to humans. The downy birch, for example, has been used “for tools, houses, fuel, food and medicine, it is home to microbes, fungi and insects central to the food chain and is critical for sheltering other plants needed to make a forest.” Rawlence evokes the natural world in lyrical, delicate prose: the “eerie and unending” dawn in Norway; the “noble air” of the larch; the “sprawling limbs” of the balsam poplar. On his journey, he discussed the issue with scientists, environmentalists, forestry experts, Indigenous peoples, reindeer herders, and farmers. He learned that climate change does not necessarily mean extinction but sometimes overgrowth and that temperature change can disorient animals’ movements. If reindeer, for example, don’t know when to move to winter pastures, their overgrazing can decimate a habitat. Rawlence offers no solutions for changes to come, only hope “in shared endeavor, in transformation, in meaningful work for the common good.” Harper’s botanical drawings complement the text.

A timely, urgent message delivered in graceful fashion.