| New England thoroughwort | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Asterales |
| Family: | Asteraceae |
| Genus: | Eupatorium |
| Species: | E. novae-angliae |
| Binomial name | |
| Eupatorium novae-angliae | |
| Synonyms [1] [2] | |
| |
Eupatorium novae-angliae, commonly called New England boneset, [1] New England justiceweed [3] or New England thoroughwort, [4] is a rare and endangered North American species in the family Asteraceae. It is found only in 4 counties in southern New England (Plymouth and Barnstable Counties in Massachusetts, plus Newport and Washington Counties in Rhode Island). [2] The species is listed as endangered species in both states. [4]
Specimens of Eupatorium novae-angliae have been collected for many years, classified by botanists as the more widespread species E. leucolepis , found from Long Island to Texas. More recent analysis of DNA sequence data reveals that the New England plants do not appear to be closely related to E. leucolepis.Eupatorium novae-angliae first formed as a hybrid between two other species, neither of them E. leucolepis. . [2] [5] [6] It is self-sustaining, rather than being found only where both parents are present, so various authors since 1992 have proposed treating it as a distinct species. [7] A formal renaming was published in 2005. [1] [8]
Eupatorium novae-angliae is a tall perennial sometimes over 3 feet (90 cm) tall. It has opposite, lance-shaped leaves, and flat-topped arrays of a large number of tiny flower heads. Each head has 5-7 white disc florets but no ray florets. [2]