This biography of Henry David Thoreau styled like a nature journal opens with the line, “There are four seasons in a year: Spring, Summer, Autumn, and Winter. I will begin with Spring.” Thoreau’s lifetime of observations around his home in Concord, Massachusetts, infuse every design aspect of this highly illustrated text. A dated timeline running across the bottom of each page introduces readers to the science of phenology (the timing of natural events) and shed light on Thoreau’s contributions to the study of climate change today. His attentive and detailed notes about plants and animals, day by day and from year to year, broaden the impact of his work beyond his well-known two years at Walden Pond. Pencil and watercolor illustrations, many with scientific labels, are awash on every page. Historical images of people, places, and documents provide social, political, and geographic context for Thoreau’s life and times, including his support of abolition and thoughts on Charles Darwin’s work.   (Ages 8-12)