| Author | (Small) E.E. Lamont | |
| Distribution | Mountains only, at middle to high elevations.
Northwestern VA and eastern KY, south to northern GA and possibly northeastern AL. | |
| Abundance | Weakley (2018) says often abundant at high elevations. This species was included with A. altissima in RAB (1968), and thus some confusion of identity and thus abundance between these two species might still be present with collections and photographs. The latter species is the primary one found in the lower elevations in the Mountains. | |
| Habitat | Moist to mesic morthern hardwood forests and spruce-fir forests. | |
| Phenology | Flowering and fruiting August-October. | |
| Identification | Our species of Ageratina can be told from the closely related genus Eupatorium by the greater number of florets per head [12-34 vs. 14 or fewer (most species only 5)]. In the field the heads are brighter white in Ageratina than any Eupatorium, a very useful clue. White Snakeroot (A. altissima) can be told from Appalachian Snakeroot by fewer florets per head (12-25 vs. 20-34) and shorter head bracts (3-5 mm vs. 5-7). | |
| Taxonomic Comments | Sometimes treated as a full species A. roanensis (Weakley 2020, without supporting data), though Weakley (2018) considered it as a variety. Many references include this within A. altissima.
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| Other Common Name(s) | None | |
| State Rank | S3 | |
| Global Rank | G5T3T4 [G3G4] | |
| State Status | | |
| US Status | | |
| USACE-agcp | | |
| USACE-emp | | |
