Native to the western United States and found from Oregon south through much of California.
Annual plants reproducing from seeds. They are tolerant of very dry, compacted soils and may occur in colonies along roadsides or waste areas. Flowering is in late summer and fall.
Mature plants are very tall and spindly looking, growing to over 5 feet tall. Early growth, however, is one or more densely foliated stalks, and as the plant matures it puts up long, thin stems that terminate in multiple short branches and flower heads at their ends. Stems often have long, pointed leaves alternating along their length, or they may be leafless.
The entire plant is covered with glandular hairs that exude a sticky sap that is very strong-scented, and gathers dust onto it giving the plants a dirty appearance.
Flower heads are small and in sparse clusters, but open to showy yellow flowers with reddish-purple bases. Flowers are usually at the ends of the stems, but also may occur in the leaf axils.
Characteristicts Important to Control:
Dry soils are tolerated, but plants are susceptible to cultivation and grow primarily where they are not disturbed. Physical removal is possible and preferred.