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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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Ambrosia confertiflora (Weakleaf bur ragweed)
Leander, Bruce

Ambrosia confertiflora

Ambrosia confertiflora DC.

Weakleaf Bur Ragweed, Weak Leaved Burweed, Slimleaf Bursage

Asteraceae (Aster Family)

Synonym(s): Franseria confertiflora, Franseria strigulosa, Gaertneria tenuifolia

USDA Symbol: AMCO3

USDA Native Status: L48 (N), PR (N)


From the Image Gallery

1 photo(s) available in the Image Gallery

Plant Characteristics

Duration: Perennial
Habit: Herb
Leaf Arrangement: Alternate
Leaf Margin: Entire
Leaf Base: Cuneate , Truncate
Size Notes: Up to about 5 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 , Purple
Bloom Time: May , Jun , Jul , Aug , Sep , Oct , Nov , Dec
Bloom Notes: Whitish to purplish.


USA: AZ , CA , CO , KS , NM , OK , TN , TX , UT

Wildflower Center Seed Bank

LBJWC-PM-20 Collected 2006-10-27 in Brewster County by Lady Bird Johnson Wildflower Center

1 collection(s) available in the Wildflower Center Seed Bank

Web Reference

Webref 3 - Flora of North America (2014) Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.

Additional resources

USDA: Find Ambrosia confertiflora in USDA Plants
FNA: Find Ambrosia confertiflora in the Flora of North America (if available)
Google: Search Google for Ambrosia confertiflora


Record Modified: 2022-09-28
Research By: DEW

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