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Common names: giant ragweed, horseweed, richweed, bloodweed, great ragweed

Scientific names: Ambrosia trifida (A. aptera, A. striata, A. variabilis)
 
     
 

Seasons of significant use: spring, summer (for Ambrosia spp. complex)

Characteristics: Native, annual, warm season forb to 15.0 feet. Stems erect; sap reddish in color; leaves mostly opposite, simple, usually deeply 2-5 cleft; plants monecious; staminate inflorescences in racemiform branching panicles; pistillate inflorescences in axils of bracts below staminate inflorescences. Flowers August-October.

Plant community type: Frequent in moist areas (e.g., stream banks, flood plains, ditches, etc.). Occurs primarily in open areas and wooded open edge situations. Somewhat shade tolerant.

More Plant Photos and Descriptions:
Appendix C: Plants by Common Name
Appendix C: Plants by Scientific Name
Appendix C: Plants Listed by Family

 
         
       
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