Torrey, in the meantime, had planned A Flora of the Northern and Middle United States, or a Systematic Arrangement and Description of all the Plants heretofore discovered in the United States North of Virginia, and in 1824 began its publication in parts, but it was soon suspended owing to the general adoption of the natural system of Antoine Laurent de Jussieu in place of that of Carl Linnaeus.
Torrey havde i mellemtiden planlagt en A Flora of the Northern and Middle United States, or a Systematic Arrangement and Description of all the Plants heretofore discovered in the United States North of Virginia, og i 1824 indledte han udgivelsen af den i enkeltdele, men den blev snart standset på grund af den udbredte tilslutning til Antoine Laurent de Jussieus naturlige system i stedet for Linnés.