Charles K. Reed introduced his collection “Nature Guides” in color.
The 4-color process was then a common printing technique that would change the publication of nature books. Charles mentions it in his introduction.
Starting then, all books published by Chester A. Reed used the 4-color process technology. However, the printing quality varied from one book to another. It did not honor the quality of Chester A. Reed’s artwork.
Here is the Gallery for the 16-page catalog. The last picture is the original drawing of the cover page.
You can consult the slideshow of the presentation.
I calculated the printing date of the catalog on whether Chester’s books were included or not. (Note on the website’s author)