Dyer's Woad

dyers woad seed

Dyer's Woad

Isatis tinctoria

Information Sheet (PDF)

Colorado List A - Eradication required


General

  • Colorado List A - Eradication required
  • Family: Mustard Brassicaceae
  • Introduced from Eurasia


Habitat

  • Annual, biennial or short-lived perennial
  • Found in rangelands, pastures, open areas, roadsides and disturbed areas
  •  Herbaceous


Plant


Vegetation

  • Leaves alternate, 1 - 4 inches long, with white mid-rib
  • Mature plants 1 - 4 feet tall


Roots

  • Lateral roots to 2 feet long
  • Taproot 3 - 4 feet long


Flower

  • 1/4 inch wide
  • Four petals
  • Season: April  to September
  • Yellow


Seed

  • 300 - 500 per plant
  • In 3/8 inch long seedpod, drooping


Seedling

  • Rosette


Reproduction

  • Seed


Control


Biological

  • None


Chemical


Cultural

  • Prevention - maintain health of site
  • Removal - bag and dispose of plants if seeds have started to develop


Mechanical

  • Burning - N/A
  • Grazing - N/A
  • Mowing- Young plants prior to 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.