Perennial Pepperweed

perennial pepperweed habit
perennial pepperweed flower
perennial pepperweed plant

Perennial Pepperweed

Lepidium latifolium

Information Sheet (PDF)


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

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


Plant


Vegetation

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


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


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. No specific recommendation or endorsement is made or implied by listing methods or products.