OF THE CAROLINAS & GEORGIA

Spermatophytes (seed plants): Angiosperms (flowering plants): Eudicots: Core Eudicots: Asterids: Campanulids: Asterales

WEAKLEY'S FLORA (2/8/20):
Erigeron canadensis   FAMILY Asteraceae   NEW! Click to go to FSUS key


SYNONYMOUS WITH PLANTS NATIONAL DATABASE:
Conyza canadensis var. canadensis   FAMILY Asteraceae

SYNONYMOUS WITH VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 179-44-008a:
Erigeron canadensis var. canadensis   FAMILY Asteraceae

SYNONYMOUS WITH Gray's Manual of Botany (Fernald, 1950)
Erigeron canadensis

SYNONYMOUS WITH Manual of the Southeastern Flora (Small, 1933, 1938)
Leptilon canadense

 

COMMON NAME:
Common Horseweed


         To see larger pictures, click or hover over the thumbnails.

image of Erigeron canadensis, Common Horseweed

USDA-NRCS PLANTS Database / Britton, N.L., and A. Brown. 1913    pnd_leca16_001_lvd

        

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_828

July    Spartanburg County    SC

Leaves alternately spiraling, numerous and crowded along stem, per Forest Plants of the Southeast and Their Wildlife Uses.

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_831

July    Spartanburg County    SC

Pappus bristles white to tan, capillary, 2-2.3mm long, per Vascular Flora of the Carolinas.

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_835

July    Spartanburg County    SC

Stem coarsely spreading-hirsute (vs E. pusillus stem glabrous or widely scattered appressed hairs), per Weakley's Flora.

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_837

July    Spartanburg County    SC

The inflorescence is a large open panicle bearing a great many small heads, per Wildflowers of the Southern Mountains.

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_839

July    Spartanburg County    SC

Stem leaves sessile, long-ciliate particularly toward base, base attenuate, per Vascular Flora of the Carolinas.

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_854

July    Spartanburg County    SC

Phyllaries green-tipped or white-tipped (vs. those of E. pusillus purple-tipped), per Weakley's Flora (2022).

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm120727_858

July    Spartanburg County    SC

The involucre is 1/8" high, and the whitish rays are narrow, short and erect, per Wildflowers of the Southern Mountains.

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm220722_9269

July    Greenville County    SC

E. pusillus on the left, E. canadensis on the right.

image of Erigeron canadensis, Common Horseweed

Gill Newberry    gn08_c_canadensis_inf

August        

image of Erigeron canadensis, Common Horseweed

Gill Newberry    gn08_c_canadensis_plant

August        

image of Erigeron canadensis, Common Horseweed

Gill Newberry    gn08_e_conyza_canadensis

August        

image of Erigeron canadensis, Common Horseweed

Gill Newberry    gn08_e_conyza_inf

August        

image of Erigeron canadensis, Common Horseweed

JK Marlow    jkm130824_548

August    Spartanburg County    SC

Stem spreading pubescent, rarely glabrous (whereas var. pusillus is glabrous), per Vascular Flora of the Carolinas.

image of Erigeron canadensis, Common Horseweed

Gill Newberry    gn09_e_conyza_habitat

September        

 

WEAKLEY'S FLORA (2/8/20):
Erigeron canadensis   FAMILY Asteraceae

SYNONYMOUS WITH PLANTS NATIONAL DATABASE:
Conyza canadensis var. canadensis   FAMILY Asteraceae

SYNONYMOUS WITH VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 179-44-008a:
Erigeron canadensis var. canadensis   FAMILY Asteraceae

SYNONYMOUS WITH Gray's Manual of Botany (Fernald, 1950)
Erigeron canadensis

SYNONYMOUS WITH Manual of the Southeastern Flora (Small, 1933, 1938)
Leptilon canadense

 

Find by SCIENTIFIC NAME:

526

Forb
Annual

Native to the Carolinas & Georgia

Common

Habitat: Old fields, disturbed areas, roadsides, gardens, per Weakley's Flora

map
NEW! Click here to see a map from Weakley's Flora of the Southeastern US showing range and abundance.

Click here to see a map showing all occurrences known to SERNEC, a consortium of southeastern herbaria. (Zoom in to see more detail.)

LEAVES:
Simple
Alternate (basal leaves usually absent or withered at flowering)

FLOWER:
Summer/Fall
Rays: White/Lavender (few, 1-2mm long)
Disc: Yellow/Yellowish
Disc flowers bisexual & fertile/ Ray flowers pistillate & fertile
Inferior ovary

FRUIT:
Summer/Fall
Yellowish
Achene

 

TO LEARN MORE about this plant, look it up in a good book!



 


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