“Lines of the geography of plants,” from On the Distribution of Plants by Alexander von Humboldt, 1817. Book in the Public Domain.
"Burchfield has exacted a quality that we may call poetic, romantic, lyric, or what you will. By sympathy with the particular, he has made it epic and universal." - Edward Hopper, who was friends with Burchfield (both were represented by the Frank K.M. Rehn Galleries in New York).