Most middle-class girls growing up in the 1860s were not encouraged to study science or actively work outside, but Katherine Sessions did both, graduating from the University of California in 1881. She especially loved trees, but found few in San Diego where she worked as a teacher. While most assumed nothing would grow in the desert climate, Kate did the necessary research, traveling and writing letters in her hunt for plants suitable to the environment. With the help of volunteers, Kate spearheaded a drive to plant thousands of trees in preparation for the Panama-California Exposition to be held in San Diego in 1915. After successfully creating a plant-rich environment in Balboa Park for the Exposition, Kate Sessions continued to pursue her passion for gardening for the rest of her life. Jill McElmurry's gouache illustrations track the gradual transformation of a sandy-brown setting to one of lush green. (Ages 5-8)