Asteraceae

Smallflower thoroughwort

Eupatorium semiserratum DC.

Family: Asteraceae
Genus: Eupatorium

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Smallflower thoroughwort (Eupatorium semiserratum) — FlowerPhoto: Will McFarland, CC BY 4.0, from iNaturalist

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Common names

By language (1)

English: Smallflower thoroughwort

Synonyms

Eupatorium cuneifolium var. semiserratum Fernald & Griscom
Eupatorium parviflorum Elliott
Eupatorium parviflorum var. monticola Whittem.
Eupatorium parviflorum var. parviflorum
Eupatorium semiserratum var. semiserratum
Uncasia semiserrata Greene

Flowers

In flower: August to October (from 67 flowering iNaturalist observations worldwide)

Characteristics

Growth habit: Forb/herb
Lifespan: Perennial
In the US and Canada: Lower 48 states: native

Photos

FlowerPhoto: Will McFarland, CC BY 4.0, from iNaturalist
FlowerPhoto: Sam Kieschnick, CC BY 4.0, from iNaturalist
FlowerPhoto: Michelle W. （鍾偉瑋）, CC BY 4.0, from iNaturalist
FlowerPhoto: Lauren McLaurin, CC BY 4.0, from iNaturalist
Photo: no rights reserved, CC0, from Wikimedia Commons
Photo: Becky Dill, CC0, from iNaturalist
Photo: Laura Clark, CC BY 4.0, from iNaturalist
Photo: Laura Clark, CC BY 4.0, from iNaturalist
Photo: Scott Ward, CC BY 4.0, from iNaturalist
Photo: Becky Dill, CC0, from iNaturalist
Photo: John Michael, CC BY 4.0, from iNaturalist
Photo: Hayes Valentine, CC BY 4.0, from iNaturalist

More in Eupatorium

Sources: classification, synonyms from World Flora Online Plant List (2026-06, CC0 1.0); common names, popularity from Wikidata (2026-10-26, CC0 1.0); common names, US characteristics from USDA PLANTS Database (2025-05-29, CC0 1.0). About our plant data.