Identification:
- Life cycle: Biennial.
- Growth Form: Forb
- Flower: Bright yellow; late spring.
- Seeds/Fruit: Seedpods are black or purplish-brown with a single seed.
- Leaves: Basal rosette leaves are 3 to 4 inches long, and are lance-shaped and connected to the stem with a petiole. The upper stem leaves are simple, alternate, bluish green with a whitish nerve on the upper surface. These leaves clasp the stem with an ear-like projection, and decrease in size toward the top of the stem.
- Stem: Erect; 1 to 4 feet in height.
- Root: Thick taproot plus roots near soil surface.
- Propagation: Mainly by seed, which germinate in the fall or early spring, and develop rosettes that produce large taproots during the first year. The following spring, new leaves grow from the crown bud in the rosette, and bolting begins. (CSU 2000) (Belliston et al. 2004).
Control:
Hand pulling is the simplest and most effective method of control. The taproot may be as deep as 5 feet and so removing as much of it as possible is important to effective control. Plant pieces must be carefully bagged and disposed of, particularly the seed.
Cautions:
Synonyms: