Isatis tinctoria

Species category

Weed

Common name

Dyer's woad

Diagnostic characters

Planting unit

SiliqueSilique:
A fruit usually dehiscing by two lateral valves (having a central septum). The fruits can be long or short in length and round or flat in cross section. Contains more than one seed. Found in Brassicaceae.

Shape

OvalOval:
Broadly elliptic.
to obovateObovate:
Inverted egg shaped with apical end the broadest.

Size

  • Length 9–12 mm
  • Width 3–5 mm
  • Thickness 1.5–2 mm

Color

Dark lavender

Texture

Shiny and wrinkled

Other structures

SiliqueSilique:
A fruit usually dehiscing by two lateral valves (having a central septum). The fruits can be long or short in length and round or flat in cross section. Contains more than one seed. Found in Brassicaceae.
has a remnant of the pedicelPedicel:
The stalk within an inflorescence supporting a single flower or spikelet.
and a longitudinal line in the center.

Identification notes

SiliqueSilique:
A fruit usually dehiscing by two lateral valves (having a central septum). The fruits can be long or short in length and round or flat in cross section. Contains more than one seed. Found in Brassicaceae.
does not open to release the individual seeds.

Noxious weed seed categories

State Noxious Weed: Arizona, California, Colorado, Georgia, Idaho, Kentucky, Louisiana, Missouri, Montana, Nevada, Oregon, Utah, Washington, Wyoming

AOSA examination list

Not included

Nomenclature

Family

Brassicaceae

Valid name

Isatis tinctoria L.

 Isatis tinctoria.  Lavender siliques with a longitudinal line in the center and remnants of the pedicel. 
Isatis tinctoria. Lavender siliques with a longitudinal line in the center and remnants of the pedicel. 
 Isatis tinctoria.  Lavender siliques with a longitudinal line in the center. 
Isatis tinctoria. Lavender siliques with a longitudinal line in the center.