[citation needed] 1905 saw the first appearance of North American Flora, written by Nathaniel Lord Britton and Lucien Marcus Underwood.
[citation needed] Barnhart was responsible for reviews of manuscripts including proof-reading and bibliographic correction.
[citation needed] In 1916, he became one of the two founding editors of the Garden's new botanical journal Addisonia, along with George Valentine Nash.
[citation needed] Barnhart kept a careful record of his own publications, creating a separate card catalog for them.
A complete listing of his publications appeared in the Bulletin of the Torrey Botanical Club, volume 77, pages 167 - 175.