Department Header For Noxious Weed Division
Yellowstone County, Montana
Noxious Weed
Weed Information Contact Department

Dyers Woad
(Isatis tinctoria)

Dyers Woad

Photo from Weeds of the West, revised edition.

Dyers Woad Rosetta

Dyers Woad Root

Dyers Woad Stem

Dyers Woad Leaf

Dyers Woad Bloom

Dyers Woad Seed

Photos from Montana Weed Control Association


Growth Habit: Biennial or perennial up to 3 ft. tall.

Leaves: Basal rosette leaves are long with soft fine hairs. Stem leaves alternate, have short basal lobes clasping the stem and without hair.

Stem: Woody, upper portion is branched.

Flower: Small, yellow, 4 - petaled 1/8 inch across.

Roots: It has a thick taproot, which may exceed 5 feet in depth.

Seeds: Plant has many , slightly pear-shaped, winged, black seedpods ½ inch long that hang like ornaments. Each pod contains one seed. One plant can produce 350 to 500 seeds and some plants can produce 10,000 seeds.

Reproduction: By Seed.

Habitat: Dyers Woad can be found along roadsides, disturbed areas, rangeland, and cropland areas.

Biological Control: Native Rust Pathogen (Puccinia thlaspeos)

Herbicides: Metsulfuron in combination with 2,4-D is the most effective.


Video Supplied By Montana Weed Control Association