Scotch Broom Removal (YouTube): Oregon State University Extension Service
Scotch Broom Smack Down!: Oregon State University Extension Service
FEIS: DISTRIBUTION AND OCCURRENCE: "Scotch broom was introduced to California as an ornamental in the 1850s, was widely used for roadside erosion control in the early 1900s, and was recognized as a problem in California in the 1930s"
[Wikipedia] Europe native: Cytisus scoparius (syn. Sarothamnus scoparius), the common broom or Scotch broom, is a deciduous leguminous shrub native to western and central Europe. (link added by Mary Ann Machi)
[Cal-IPC] Invasive: Cytisus scoparius (Scotch broom) is a perennial shrub (family Fabaceae), which grows in sunny sites with dry sandy soil, and spreads rapidly through pastures, borders of forests, and roadsides. Cytisus scoparius can be found from the coast to the Sierra foothills. This weed crowds out native species, has a seedbank that can remain dormant for up to 80 years, diminishes habitat for grazing animals, and increases risk for wildland fires.
Cal-IPC Rating: High (link added by Mary Ann Machi)