A Field Guide to Trees and Shrubs:

Ecologist and field naturalist George A. Petrides worked with the National Park Services and was later a professor at Michigan State University at Lansing. Petrides has written books for the Peterson's Field Guide series and was also 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. These editions include updated material by Michael O'Brien, Paul Lehman, Bill Thompson III, Michael DiGiorgio, Larry Rosche, and Jeffrey A. Gordon.