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Plant Database

Search for native plants by scientific name, common name or family. If you are not sure what you are looking for, try the Combination Search or our Recommended Species lists.

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Conyza canadensis var. canadensis (Canadian horseweed)
Stone, Robert L.

Conyza canadensis var. canadensis

Conyza canadensis (L.) Cronquist var. canadensis

Canadian Horseweed

Asteraceae (Aster Family)

Synonym(s): Erigeron canadensis, Leptilon canadense

USDA Symbol: COCAC3

USDA Native Status: L48 (N), AK (I), HI (I), CAN (N), SPM (N)

 

From the Image Gallery

3 photo(s) available in the Image Gallery

Plant Characteristics

Duration: Annual
Habit: Herb
Leaf Retention: Deciduous
Leaf Shape: Linear , Oblanceolate
Size Notes: Up to about 6 feet tall. Occasionally up to almost 12 feet tall.
Fruit: Fruit is a cypsela (pl. cypselae). Though technically incorrect, the fruit is often referred to as an achene.

Bloom Information

Bloom Color: White , Yellow , Purple
Bloom Time: Feb , Mar , Apr , May , Jun , Jul , Aug , Sep , Oct , Nov , Dec
Bloom Notes: White to pale purplish small ray flowers, yellow disc flowers. Flowers mostly summer through fall. May flower year-round in the right conditions.

Distribution

USA: AK , AL , AR , AZ , CA , CO , CT , DC , DE , FL , GA , HI , IA , ID , IL , IN , KS , KY , LA , MA , MD , ME , MI , MN , MO , MS , MT , NC , ND , NE , NH , NJ , NM , NV , NY , OH , OK , OR , PA , RI , SC , SD , TN , TX , VA , VT , WA , WI , WV , WY
Canada: AB , MB , NB , NL , NS , NT , ON , PE , QC , SK

Growing Conditions

Soil Moisture: Dry , Moist

National Wetland Indicator Status

Region:AGCPAKAWCBEMPGPHIMWNCNEWMVE
Status: FACU UPL FACU FACU FACU FACU UPL FACU FACU FACU
This information is derived from the U.S. Army Corps of Engineers National Wetland Plant List, Version 3.1 (Lichvar, R.W. 2013. The National Wetland Plant List: 2013 wetland ratings. Phytoneuron 2013-49: 1-241). Click here for map of regions.

Web Reference

Webref 38 - Flora of North America (2019) Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
Webref 23 - Southwest Environmental Information Network (2009) SEINet - Arizona Chapter

Additional resources

USDA: Find Conyza canadensis var. canadensis in USDA Plants
FNA: Find Conyza canadensis var. canadensis in the Flora of North America (if available)
Google: Search Google for Conyza canadensis var. canadensis

Metadata

Record Modified: 2022-12-06
Research By: TWC Staff

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