Download (PDF 221 KB): https://research.fs.usda.gov/download/treesearch/36955.pdf
Abstract
Scotch broom (Cytisus scoparius: (L.) Link), a native European perennial shrub, was introduced to the U.S. before the turn of the century as an ornamental for its bright yellow, pea-like flower. The plant found the western U.S. maritime zone to be an ideal habitat, thus it soon escaped from cultivation, and became an invasive weed now widely distributed from northern California to British Columbia. The massive monocultures that Scotch broom forms replace desirable species and cause allergy problems when flowering in spring. This has elevated it to one of the most important weeds in the northwest coast of the U.S.A. (Parker et al., 1994; Radtke and Davis, 2000).
Citation
Markin, George P.; Horning, Carol J. 2010. Discovery of a gall-forming midge, Asphondylia pilosa Kieffer (Diptera: Cecidomyiidae), on Scotch broom (Cytisus scoparius (L.) Link) Fabaceae). Journal of the Kansas Entomological Society. 83(3): 260-263.