Dyer's Woad
Isatis tinctoria

Dyer's Woad adult
Dyer's woad may be a winter annual, biennial, or a short-lived perennial. Heights of one to four feet are common. A thick tap root may penetrate to five feet deep.
Dyer's Woad rosette
Leaves are blue-green with a whitish midrib.
Weed Infestation
Dyer's Woad infestation
Dyer's woad was introduced from Europe for production of textile dyes. It thrives in waste areas, gravel pits, road sides, pastures, field edges, and disturbed soils.
Dyer's Woad flower
The bright yellow flowers bloom and are highly visible in late spring.
Dyer's Woad seed
Club shaped seed pods each produce a single seed. As the fruits mature they turn from green to dark brown or nearly black.
Biocontrol - Rust
Dyer's Woad rust
Rust infected plants have a curley puckered look and are usually smaller than surrounding woad plants. Rust is located under the leaf surface and appears as small reddish-brown spots.