Teasel

teasel seedhead
teasel-habitat-2014
teasel-rosette-2017

Teasel

Dipsacus spp.

Colorado List B - Eradication required in parts of Jefferson County

Information Sheet (pdf)

Eradication Zone Map (pdf)


General

  • Biennial
  • Family: Dipsacaceae
  • Introduced to North America in the 1700s
  • Native of Europe


Habitat

  • Found in pastures, rangeland, right-of-ways, ditch banks and disturbed areas
  • Moist to dry, fertile soil


Plant


Vegetation

  • Clasps the stem, forming cup-like structures
  • Leaves are oblong, hairy
  • Mature plants grow 2 to 8 feet tall


Roots

  • Thick tap root


Flower

  • Color: purple and white
  • Each plant produces about 3,300 seeds
  • Season: flowers June through October
  • Upward curving stiff bracts below flower heads


Seed

  • 3,300 per plant
  • May be transported by birds
  • Most germinate in the first season
  • Seed drops from mother plant


Seedling

  • Seedlings live for a year or more before bolting


Reproduction

  • Seed


Control


Biological

  • None


Chemical


Cultural

  • Prevention - maintain health of site
  • Rosette removal
  • Seed head removal and disposal


Mechanical

  • Burning - Late spring (new populations)
  • Grazing - N/A
  • Mowing - Repeated before flower formation


Use all chemicals according to the manufacturer's label. No specific recommendation or endorsement is made or implied by listing methods or products.

Treatment Timeline


JanFebMarAprMayJuneJulyAugSeptOctNovDec
Control











Removal











Herbicide











Growth











Rosette











Vegetative











Flowering











Seed