Weed ID

DYER'S WOAD

Brassicaceae or Mustard Family
Isatis tinctoria

GROWTH HABIT: Winter annual, biennial, or short-lived perennial, grows 1-3 feet tall.

LEAVES: Rosette leaves are widest near the tip and covered with soft hairs. Stem leaves usually lack hairs and teeth on the margins. Bluish-green leaves with white midrib on upper leaf surface are alternately arranged, lance-shaped and clasp the stem with short basal lobes.

STEMS: Long slender stalks

FLOWERS: The four yellow petals of an individual flower are arranged in a cross formation and are 1/8 inch long and wide. Flowers cluster on the upper portion of the stem, creating a dens flat-topped inflorescence.

ROOTS: 3-5 foot long taproot and some lateral roots in the upper 12 inches of the soil.

SEEDS: Purplish-brown, teardrop-shaped seed pods that hang from small stalks. Plants may produce 350 to 500 seeds each, but selected plants have been known to produce more than 10,000 seeds in one year.

REPRODUCES: By seed.

HABITAT: Roadsides, railroads, disturbed sites and spread from there to rangeland and cropland by seeds.

"Dyer's woad to handpull this weed"