Noxious Weeds

Noxious weeds are a major concern in the Shoshone Field Office and throughout Idaho. Because noxious weeds produce large volumes of seed and have few natural competitors, they pose a serious threat to the health of wildlife habitats, river systems and recreation areas, as well as to pastures and croplands. Once established, noxious weeds spread quickly and overtake desirable plant communities. At their current rate of spread (estimated at 14 percent per year), noxious weed populations in Idaho are expected to double in less than six years.

BLM’s Shoshone Field Office is working to identify and reduce weed infestations in south-central Idaho. The most commonly occurring weeds in Shoshone include Leafy spurge, Scotch thistle, and Spotted knapweed. The preferred treatment methods are through chemical (use of herbicides), biological (release of approved biological agents such as insects), and mechanical (physical weeding) activities. An estimated 187,850 acres in the Shoshone area are infected with noxious weeds and about 3,000-4,000 acres are treated annually to destroy these dangerous invaders.

You can help prevent the spread of noxious weeds by taking simple steps while exploring and enjoying public lands. Recreationists and other public land users should be able to identify noxious weeds, understand their danger, and take actions to prevent their spread. Boaters should clean boats and trailers, while campers and hikers should check all clothes and camping gear for seeds and clean the undersides of their cars. If a noxious weed is spotted on public lands, it is important to pull the weed up by the roots, dispose of all parts in a plastic bag and report its location and description to the nearest BLM field office or Forest Service. By taking preventative action, Shoshone will be able to maintain healthy rivers and wildlife habitats for years to come.