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Horseweed

Photo: @roberta15631 · iNaturalist · CC BY-NC

Plants

Horseweed

Erigeron canadensis

Observations in the area
2
Last sighting
24 September 2025
Category
Plants
View on iNaturalist

Species and sighting data come from the iNaturalist platform and may change over time.

The species

Erigeron canadensis (synonym Conyza canadensis) is an annual plant native throughout most of North America and Central America. It is also widely naturalized in Eurasia and Australia. Common names include horseweed, Canadian horseweed, Canadian fleabane, coltstail, marestail, and butterweed. It was the first weed to have developed glyphosate resistance, reported in 2001 from Delaware.

Text: Wikipedia · CC BY-SA

Where it has been observed

More photos

Other species in the same category

Nature data: iNaturalist

Sighting data also come from open nature platforms and may change over time.