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.

 Treatment Timetable


JanFebMarAprMayJuneJulyAugSeptOctNovDec
Control











RemovalNot recommended - will regrow from root fragments
Herbicide











Growth











Vegetative











Flowering











Seed