Verbatim text: Sudworth, G. B. 1934. Poplars, Principal Tree Willows and Walnuts of the Rocky Mountain Region. Washington. [U.S.D.A., Techn. Bull. 420.]
Author: Sudworth, G.B.
Year: 1934
Title: Poplars, Principal Tree Willows and Walnuts of the Rocky Mountain Region
Journal: U.S.D.A., Techn. Bull
Volume: 420