Gall of the Earth (Nabalus trifoliolatus Cass.)

Also known as gall-of-the-earth, three-leaved rattlesnake root, dwarf rattlesnakeroot; also classified as Nabalus nanus (Bigelow) DC., Prenanthes trifoliolata (Cass.) Fernald, Prenanthes nana (Bigelow) Torr. ex DC.

Some authorities separated this taxon into two populations, the main one under the epithet trifoliatus/trifoliata, and a "dwarf" species in NY, NH, and ME, referred to as nanus/nana. However, most modern authorities have merged the two. A few sources recognized the dwarf taxon as a variety, var. nanus/nana, but most modern authorities do not even recognize those. We merge the taxa without recognizing any sub-taxa, per POWO's treatment. Independently of this consideration, this species was moved from the Prenanthes genus into the Nabalus genus; normally it would keep the same epithet, except that in this case, the name Nabalus trifoliolatus Cass. (1825) is older than the name Nabalus nanus (Bigelow) DC. (1838). This situation is the reverse of the names in the other genus: Prenanthes nana (Bigelow) Torr. ex DC. (1838) is older than Prenanthes trifoliolata (Cass.) Fernald (1900). Hence many sources refer to Prenanthes trifoliolata and then reclassify it into Nabalus trifoliolatus.