Asteraceae

Semaphore thoroughwort

Eupatorium mikanioides Chapm.

Family: Asteraceae
Genus: Eupatorium

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Semaphore thoroughwort (Eupatorium mikanioides) — FlowerPhoto: Jay Horn, CC BY 4.0, from iNaturalist

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Common names

By language (1)

English: Semaphore thoroughwort

Synonyms

Eupatorium crassifolium Shuttlew. ex A.Gray
Uncasia mikanioides Greene

Flowers

In flower: June to August (from 14 flowering iNaturalist observations worldwide)

Characteristics

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

Photos

FlowerPhoto: Jay Horn, CC BY 4.0, from iNaturalist
FlowerPhoto: Jay Horn, CC BY 4.0, from iNaturalist
FlowerPhoto: Jay Horn, CC BY 4.0, from iNaturalist
LeavesPhoto: Erik, CC BY 4.0, from iNaturalist
Photo: Bob Peterson from North Palm Beach, Florida, Planet Earth!, CC BY-SA 2.0, from Wikimedia Commons
Photo: Kristály Cravens-Liszak, CC BY 4.0, from iNaturalist
Photo: Jochen Essig, CC BY 4.0, from iNaturalist
Photo: Keenan Pepper, CC BY 4.0, from iNaturalist
Photo: Leila Dasher, CC BY 4.0, from iNaturalist
Photo: Josiah Londerée, CC BY 4.0, from iNaturalist
Photo: Ian Talty, CC BY 4.0, from iNaturalist
Photo: Adam Pitcher, CC0, from iNaturalist

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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.