Canadian Horseweed Conyza canadensis (Linnaeus) Cronquist var. canadensis    Synonyms: Erigeron canadensis, Horseweed Fleabane, Leptilon canadense.
Kingdom Plantae   >   Division Tracheophyta   >   Class Magnoliopsida   >   Order Asterales   >   Family Asteraceae   >   Genus Conyza   

Description:

The nominate variety of Canadian Horseweed can be easily identified by checking to see if the phyllaries are green tipped. Differentiated from the pusila variety which has purple tipped phyllaries.

Relationships:

Host plant for various species of moth including Wavy-lined Emerald Moth (Database of World's Lepidopteran Host Plants).

There are 342 records in the project database.

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Canadian Horseweed in Howard Co., Maryland (9/13/2013). Photo by Bill Harms. (MBP list)

Canadian Horseweed in Caroline Co., Maryland (9/14/2020). Photo by Jim Brighton. (MBP list)

Canadian Horseweed on Assateague Island, Maryland (8/19/2012). This is an abundant roadside species in Maryland. Photo by Bill Hubick. (MBP list)

Canadian Horseweed on Assateague Island, Maryland (8/19/2012). Photo by Bill Hubick. (MBP list)

Canadian Horseweed in Prince George's Co., Maryland (8/18/2016). Photo by Bill Harms. (MBP list)

Canadian Horseweed in Caroline Co., Maryland (8/23/2016). Photo by Wayne Longbottom. (MBP list)

Canadian Horseweed in Charles Co., Maryland (9/25/2016). Photo by Wayne Longbottom. (MBP list)

Canadian Horseweed in Allegany Co., Maryland (6/6/2015). Photo by Kimberly Booth. (MBP list)

Canadian Horseweed in Allegany Co., Maryland (6/6/2015). Photo by Kimberly Booth. (MBP list)

Canadian Horseweed in Caroline Co., Maryland (8/28/2016). Photo by Wayne Longbottom. (MBP list)

Canadian Horseweed in Baltimore Co., Maryland (8/24/2016). Photo by Kirsten Johnson. (MBP list)


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