CONTENTS 
     
    Registerd Herbicides 
     
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    Identification] 
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    General Description: 
    
      - grows upright to a height of 2-3 feet, with hairy
        upper stems.
 
      - reddish coloring on lower stems and taproot.
 
      - leaves are alternate and simple.
 
      - reddish-green leaves with long petioles and prominent
        veins.
 
      - small, green flowers arranged in dense terminal
        clusters  (small clusters may be present in leaf axils).
 
      - acts as a host for the beet leafhopper.
 
     
    Life cycle:     summer
    annual  
      - seeds are glossy, black, and rounded with convex sides
        - produced late summer through fall.
 
      - reproduction is only by seed.
 
      - germination - spring through summer.
 
        Seedlings: cotyledons are narrow and pointed with a bright red underside. 
     
    Impact on Yield: 
      - In one study, a redroot pigweed infestation of 10
        plants per square foot caused a peppermint oil yield reduction of 34.3 lbs per acre (Ian
        Heap).
 
     
    Habitat/ Distribution:  
      - throughout western states in crops associated with
        cultivated soils, gardens, and waste areas.
 
      - especially abundant in warm climates.
 
      - introduced from tropical America.
 
     
    Herbicide Control Notes: 
      - Goal usually not persistent enough to provide adequate
        control, and higher rates often cause crop injury. Sinbar will control nonresistant
        strains. Gramoxone cannot be used in actively growing mint. Tough provides the most
        effective postemergence control.
 
     
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