Note 1 — Cavity-Nesting Birds of North American Forests
Reading edition
Scott, Virgil E. Characteristics of ponderosa pine snags used by cavity-nesting birds. U.S. Fish and Wildlife Service, Fort Collins, Colorado.
Reading edition
Scott, Virgil E. Characteristics of ponderosa pine snags used by cavity-nesting birds. U.S. Fish and Wildlife Service, Fort Collins, Colorado.