[Cal-IPC] Invasiveness. Mediterranean region native.: Asphodelus fistulosus (onion weed) is an annual/perennial herb (family Liliaceae) found in dry, sandy and rocky places, as well as pastures, roadsides and waste places. Livestock avoid eating it, allowing it to create dense stands that crowd out more desirable forage species in pastures. It is primarily found along coastal regions of Southern California. (link added by Mary Ann Machi)
[Wikipedia] Mediterranean Native, Invasive Exotic Weed Status: It is native to the Mediterranean region. It is an invasive exotic weed in the United States, with significant infestations in California, Arizona, New Mexico, and Texas. It is listed as a Federal Noxious Weed by the United States Department of Agriculture. (link added by Mary Ann Machi)