The Peterson Field Guides (PFG) are a popular and influential series of American field guides intended to assist the layman in identification of birds, plants, insects and other natural phenomena. The series was created and edited by renowned ornithologist Roger Tory Peterson (1908–1996). His inaugural volume was the classic 1934 book A Field Guide to the Birds, published (as were all subsequent volumes) by the Houghton Mifflin Company.