Yellow starthistle continues its spread in California

Abstract

Yellow starthistle is an exotic invasive weed that is estimated to infest over 14 million acres in California and is considered the most common exotic weed statewide. We reviewed several previous studies and conducted a township survey to provide an up-to-date analysis of the weed's rapid spread throughout the state. A county-by-county comparison between 1985 and 2002 showed increases in yellow starthistle in all regions of the state except for northeast California and the southeast desert region. Currently, most infestations occur in Northern California, but future invasions and spread will likely occur in the coastal counties of Southern California.

Physiological host range of Ceratapion basicorne, a prospective biological control agent of Centaurea solstitialis (Asteraceae)

“…The weed infests about eight million hectares in the western US and Canada (Duncan, 2001;Pitcairn et al, 2006). Infestations have been reported in 23 states, with the largest populations in the states of California, Idaho, Oregon, and Washington (Maddox et al, 1985;Sheley et al, 1999).…”

“…Infestations have been reported in 23 states, with the largest populations in the states of California, Idaho, Oregon, and Washington (Maddox et al, 1985;Sheley et al, 1999). It is considered the most common weed in California, and it is continuing to spread and threaten states to the east (Pitcairn et al, 2006). The weed is designated as noxious in 11 western states and two Canadian provinces (Skinner et al, 2000).…”

Using Expert Knowledge to Satisfy Data Needs: Mapping Invasive Plant Distributions in the Western United States

“…within the Great Basin. Pitcairn et al (2006) combined roadside surveys with expert opinion to map distribution and abundance of Centaurea solstitialis in California townships. Finally, the Colorado Department of Agriculture (http://www .colorado.gov/ag/csd) conducts regular surveys of county weed managers for over 20 invasive species.…”

Applying the Successional Weed Management Model for Revegetating a Yellow Starthistle-Infested Dryland Pasture in the Chihuahuan Desert

“…Yellow starthistle (Centaurea solstitialis) is an exotic annual forb that was introduced into California in the mid-1800's and has since become widely distributed across the Western USA [1][2][3]. Legally designated as a noxious weed in 12 western states, yellow starthistle is a major problem in California where it has infested up to 22 million acres or about 22% of the state's surface area [4].…”