Noxious weeds are non-native plants introduced to North America from Europe and Asia. These plants have spread at an alarming rate because, unlike native species, there are no native insects, fungi, or diseases to control their growth and spread in this country. What began as a handful of plants introduced in the 19th century, now number in the hundreds of millions. Noxious weeds destroy wildlife habitat and forage, threaten endangered species and native plants, increase erosion and groundwater loss, and prevent recreational activities.
Estimates indicate that noxious weeds are spreading at rate of 4,600 acres per day on federal lands alone in the western United States. They have invaded approximately 17 million acres of public rangelands in the West -- more than quadrupling their range from 1985 to 1995. In northern California, yellow starthistle expanded its range from 1 million acres in 1981 to 10 million acres in 1997.
The Bureau of Land Management is just one of many government agencies mounting an effort to control and prevent noxious weeds, as well as educate the public about how destructive these plants can be. In the Central Coast Field Office there are several noxious weed species that are of concern and being addressed using different techniques.
The information presented here is taken from Selected Noxious Weeds of Northeastern California, a joint project of the Bureau of Land Management, U.S. Forest Service, Lassen County, Modoc County, Northern Deputy Agricultural Commissioners and Sealers Association, Tuscarora Gas Transmission Company, and the California Department of Food and Agriculture.