U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT
|Arcata Field Office|
Invasive Noxious Weeds
This plant guide identifies 22 noxious weeds that are known to occur on public land administered by the Bureau of Land Management's Arcata Field Office, located in northwestern California. To view more information on an individual plant, click on the plant's photograph or common name below.
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 governement agencies mounting an effort to control and prevent noxious weeds, as well as educate the public about how destructive these plants can be.