BACKGROUND: Dyer's woad was introduced from Europe for pr0oduction of textile dyes. It thrives in waste areas, gravel pits, road sides, pastures, field edges, and disturbed soils.
Other common names: Woad
DESCRIPTION: 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. Leaves are blue-green with a whitish midrib. The bright yellow flowers bloom and are highly visible in late spring. Club shaped seed pods each produce a single seed. As the fruits mature they turn from green to dark brown or nearly black.
CONTROL: Biocontrol rust fungus is naturally wide spread and other agents are currently undergoing research. Rust infected plants will have yellowish puckered leaves with dark spots on the underside. Herbicides can offer good to excellent control when applied to rosettes in spring and fall and during pre-bloom. Digging offers good control. Contact your local state or county weed specialist for specific updated information.
Photos and text taken from Noxious Weed Field Guide for Utah
