header background image
Current Weather 45° F
  • Jefferson County Parks Banner
  • Noxious Weed Identification List

    Perennial Pepperweed


    (Lepidium latifolium)

    Info Sheet Adobe PDF Icon

    Colorado List B - Control required in Jefferson County

    General

    • Family: Mustard (Brassicaceae)
    • Introduced from Eurasia, possibly as a seed contaminate

    Common names

    • Tall whitetop

    Habitat

    • Perennial, colony-forming forb
    • Tolerates saline conditions
    • Invades wetlands, riparian areas, ditch banks, roadsides, pastures and ornamental plantings

    PLANT

    Vegetation

    • Leaves: Alternate, lance-shaped, entire to toothed, bright-green to gray-green, waxy.  Lower leaves larger than upper
    • Stems: old stems form dense semi-woody clumps
    • Plants: 2 to 4 feet tall

    Roots

    • Both deep and lateral roots
    • Form semi-woody crown at soil surface

    Flower

    • Color: white, dense clusters at the ends of branches
    • Season: Early summer through August

    Seed

    • June to August

    Reproduction

    • Seed and roots; roots have growth buds

    CONTROL

    Biological

    • None

    Chemical

    • Bolting to early flower stages (early spring to early summer): Chlorsulfuron (Telar) 
    • Bolting stage (spring): Metsulfuron (Escort XP) 
    • Flower to late-flower stages (early to mid-summer): Imazapic (Plateau) 
    • Spring or fall (retreatment will be necessary): Glyphosate (RoundUp, Rodeo) 

     

    Cultural

    • Prevention – maintain health of site
    • Removal is not recommended; may spread by breaking off root fragments
    • Reseed area with desirable vegetation

    Mechanical

    • Burning  - Not effective alone. Burning standing dead plants, followed by herbicide treatment to new growth is sometimes effective 
    • Grazing  - N/A 
    • Mowing  - Spring mowing, followed by herbicide treatment 

     

    More Information


    Use all chemicals according to the manufacturer's label. Listing the above methods or products does not imply a specific recommendation or endorsement.



    Alicia Doran
    Weed & Pest Management Specialist
    303-271-5989
    adoran@jeffco.us

    weed-pest-b-perennial-pepperweed-flower

    weed-pest-b-perennial-pepperweed-plant

    weed-pest-b-perennial-pepperweed-habit


    Last Updated: 7-31-2013