When our "witness tree" first rooted beside a low stone wall in rural Massachusetts, cars were just appearing on the roads. In the life of this one grand oak, we can see for ourselves the results of one hundred years of rapid environmental change. It's leafing out earlier, and dropping its leaves later as the climate warms. Even the inner workings of individual leaves have changed to accommodate more CO2 in our atmosphere.

Climate science can seem dense, remote, and abstract. But through the lens of this one tree, it becomes immediate and intimate. In Witness Tree, environmental reporter Lynda Mapes takes us through a year with the tree in the Harvard Forest. We learn about carbon cycles and leaf physiology, but we also experience seasons of change as people have for centuries, watching for each new bud, and listening for each new bird and frog call. Lynda takes us high into the oak's swaying boughs, cores deep into its heartwood, and digs into its roots and teeming soil. She brings us eye level with garter snakes and newts, and alongside the squirrels and jays devouring the oak's acorns.

Though stark in its implications, Witness Tree is a beautiful and lyrical read, rich in detail, sweeps of weather, history, people, and animals. It's an inescapable document of climate change, but also an environmental story rooted in hope, beauty, wonder, and the possibility of renewal in people and the world around us.