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horseweed
Erigeron canadensis
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.
Where it lives
Recorded sightings
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geo-referenced records in GBIF, from museums, herbaria and field observers.
Drag the globe to turn it. Dots are where records exist, not a range map; darker means more records.
In the stacks
Searching the stacks…
Every page naming Erigeron canadensis in the Biodiversity Heritage Library →
This page is assembled live from iNaturalist, GBIF, Wikipedia, the Source Library and the Internet Archive. It is not yet part of the hand-edited codex. iNaturalist taxon 76907.