Isatis tinctoria

Isatis tinctoria_Dyers woad_JM DiTomaso
Photo: Joseph DiTomaso

Common names: dyer's woad

Isatis tinctoria (dyer’s woad) is a winter biennial or short-lived annual herb/forb (family Brassicaceae). Plants are highly competitive and often grow in dense colonies. It can be found distributed among the Klamath, Cascade, and North Coast Ranges, northern & central Sierra Nevada, Modoc Plateau, and northern San Francisco Bay region. Dyer’s woad is a noxious weed of rangeland, agronomic crops, and undisturbed natural areas.

Cal-IPC Rating: Moderate

CDFA Rating: B*

Cal-IPC Assessment

Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.

Species ID Card

Invasive Species ID Card - To support field identification of early detection species, Cal-IPC has designed a set of Species ID cards that can be downloaded, printed double-sided, and trimmed to size.

Weed Management Notes

  • Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

Other Isatis tinctoria Information

  • CalPhotos - Images of plants taken mostly in California.
  • Calflora - See the distribution of this species on Calflora's map of California.
  • CalWeedMapper - Distribution information with ability to determine regional priorities.
  • Jepson Online Interchange for California Flora - Information on taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
  • CDFA - California official noxious weeds.
  • USDA PLANTS Database - Federal database with information on identification and distribution, and links to websites in individual states.
  • EDDMapS - North American distribution based on Early Detection and Distribution Mapping System.
  • Additional photos

    Isatis tinctoria_dyer's woad_growth habit_Bob Case_cropped
    Isatis tinctoria, dyer's woad, growth habit. Photo: Bob Case
    Isatis tinctoria_dyer's woad_inflorescense_Bob Case_cropped
    Isatis tinctoria, dyer's woad, inflorescense. Photo: Bob Case