| Author | de Candolle | |
| Distribution | Southeastern Piedmont and Sandhills; disjunct to Jones County. The Mecklenburg County specimen needs careful ID. One of the Taxon Editors (Sorrie) has encountered this plant a number of times in the Sandhills region, where it is always associated with loamy sandy soils and acts like a native species in natural habitat. Sorrie suggests that the NC occurrences be treated as a native species, unless subsequent data proves otherwise.
MI to MT, south to LA and NM; scattered eastward to the Atlantic seaboard. Mexico. Some references treat the more eastern populations as adventive. | |
| Abundance | Uncommon to locally numerous in the Sandhills region, but can be abundant where found; plants tend to form colonies. Very rare to rare away from the Sandhills. The NCNHP treats this species as non-native and provides no State Rank. As Weakley (2018) does consider it native in NC, the website editors suggest a State Rank of S2S3. | |
| Habitat | Mesic to dry, usually loamy soil of Longleaf Pine--Wiregrass flats and pea swales, "sandy oak woodland near Island Creek" (Jones Co.), "mesic roadside in Triassic Basin" and "railroad cinder bed" (both Anson Co.). Well-adapted to fire. | |
| Phenology | Flowering and fruiting September-October. | |
| Identification | While all naturalists know Common Ragweed (A. artemisiifolia), very few know Perennial Ragweed. Its aspect is closely similar to the former, but it is usually half as tall and is perennial from long, slender, horizontal rhizomes. It has only pinnate-pinnatifid leaves instead of bipinnate-pinnatifid in Common Ragweed; thus, the leaves are less lacy-cut and the ultimate lobes are rounded and not rather pointed as in Common Ragweed. The leaves tend to look narrowly triangular instead of broadly triangular as in Common Ragweed. Also note the very specific habitat and fire tolerance. | |
| Taxonomic Comments | A synonym is A. rugelii. Weakley (2018) includes the two species in RAB (1968) -- this one and A. rugelii -- into A. psilostachya now.
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| Other Common Name(s) | Cuman Ragweed, Western Ragweed | |
| State Rank | [S2S3] | |
| Global Rank | G5 | |
| State Status | | |
| US Status | | |
| USACE-agcp | FAC link |
| USACE-emp | FAC link |
