- Isatis tinctoria is a biennial member of the mustard family that can grow from 1-4 ft. (0.3-1.2 m) tall.
- First years growth is represented by a rosette of hairy, bluish-green leaves 1.5-7 in. (3.7-18 cm) long. Stem leaves are lance-shaped and alternate with a cream colored mid-rib.
- Flat-topped yellow flowers with four spoon shaped petals appear in small clusters at the top of the stems. Flowering occurs in spring to late summer.
- Seed pods are black or purplish, flattened, 0.4 in. (0.9 cm) long, 0.25 in. (0.6 cm) wide and hang from short stalks at the ends of the stems.
- Ecological Threat
- Isatis tinctoria occurs in areas with poor, dry soils such as roadsides, rangelands and open forests. Isatis tinctoria is native to central Asia and northern Russia and was introduced to North America in the early 1900’s as a contaminant in alfalfa seed.
- Zouhar, Kris. 2009. Isatis tinctoria. Fire Effects Information System, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory
- King County Department of Natural Resources and Parks Water and Land Resources Division
- Oregon Department of Agriculture Plant Programs, Noxious Weed Control
- Washington State Noxious Weed Control Board
- University of California, Jepson Flora Project
- Nevada Department of Agriculture
- California Invasive Plant Council
- USDA NRCS PLANTS
- USDA ARS GRIN