Peterson First Guide to Trees of North America

George A. Petrides, ecologist and field naturalist, worked with the National Park Services and taught at Michigan State University at Lansing. Petrides has written for the Peterson Field Guide series and was the recipient of an award from the Federated Garden Clubs of Michigan for A Field Guide to Trees and Shrubs .

ROGER TORY PETERSON, one of the world's greatest naturalists, received every major award for ornithology, natural science, and conservation as well as numerous honorary degrees, medals, and citations, including the Presidential Medal of Freedom. The Peterson Identification System has been called the greatest invention since binoculars. Janet Wehr, RN, devoted much of her nursing career to hospice care. Wehr has served as a member of the Therapeutic Touch International Association, the American Holistic Nurses Association, and the Saret Charitable Fund of DuPage County, IL.