Robert W. Freckmann Herbarium


  Ambrosia trifida L. var. trifida image
Photographer: Paul Drobot           

Botanical Illustration

Botanical Illustration

Emmet J. Judziewicz

Matthew L. Wagner

Merel R. Black

Merel R. Black

Merel R. Black

Christopher Noll

Paul Drobot

Paul Drobot

Robert W. Freckmann

Robert W. Freckmann

Robert W. Freckmann
Family Asteraceae
Ambrosia trifida L. var. trifida
giant ragweed, great ragweed, horse-cane
Ambrosia: Greek for "food of the gods"
trifida: three-cleft
County distribution map- click for detailed distribution maps.
Detailed Distribution:
Town Range Maps
Google Dot Maps
Status: Native - potentially invasive
Plant: erect, annual, 2'-9' tall forb
Flower: inflorescence of many, small, green, bead-like heads on 10" spikes; blooms Aug.-Sept.
Fruit:seeds not on fluffy pappus
Leaf:opposite, stalked, 3-5 palmately-divided lobes, upper leaves slightly winged
Habitat: moist; disturbed sites
(Glossary)

More Information Natural Communities Herbarium Specimens
All Ambrosia list Ethnobotany Information Google- Images or Text

Flora of North America (off site)
Synonyms 
Ambrosia integrifolia Muhl. ex Willd.
Ambrosia striata Rydb.
Ambrosia trifida L. var. integrifolia (Muhl. ex Willd.) Torr. & A.Gray
Ambrosia variabilis Rydb.

         
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