Lost Rivers Cooperative Weed Management Areaupdated: June 2015

The Lost Rivers Cooperative Weed Management Area covers approximately 2.1 million acres of the Big and Lost River Valleys including all of Butte County and portions of Custer and Lemhi Counties. The purpose of the Lost Rivers CWMA, as per the Strategic Plan, is “To defend the landscape of the Lost River Valleys from invasion by exotic plants and noxious weeds.” To assist in this objective the LRCWMA seeks participation of all who have a vested interest or responsibility in protecting these resources.

A majority of the LRCWMA is federally managed by the Bureau of Land Management, the U.S. Forest Service, the National Park Service and the Department of Energy. Representatives from each of these agencies are actively involved within the LRCWMA and have dedicated programs committed to the management of noxious weeds. Butte, Custer and Lemhi Counties are engaged, through respective weed departments, in supporting the CMWA. Numerous private landowners actively participate in LRCWMA noxious weed control projects by helping to identify and manage noxious weed infestations.

The presence and prevalence of noxious weeds varies throughout the LRCWMA. Prioritization of the use of limited resources for noxious weed control is based upon several factors including the potential for spread, rate of spread, species prevalence in an area and practicality in controlling a species. Management and priority of the various noxious weed species occurring within the LRCWMA varies within species of primary concern are (in order of prevalence):

  1. Canada Thistle
  2. Leafy Spurge
  3. Spotted Knapweed
  4. Whitetop
  5. Russian Knapweed
  6. White Bryony
  7. Black Henbane
  8. Houndstongue
  9. Scotch Thistle
  10. Musk Thistle
  11. Diffuse Knapweed
  12. Rush Skeletonweed
  13. Saltcedar
  14. Yellow Toadflax
  15. Perennial Pepperweed
  16. Dalmatian Toadflax
  17. Dyer’s Woad

Weed Superintendents

  • Custer County
    • Casey Kristofferson          
    • custercoweeds@custertel.net
    • P.O. Box 385           
    • Challis, Idaho 83226
    • Office Phone: 208-879-5229       
    • Fax: 208-879-6413       
    • Cell: 208-833-5229
  • Lemhi County
    • Jeremey Varley (Webmaster)       
    • weeds@lemhicountyidaho.org
    • 200 Fulton St. Ste 201   
    • Salmon, Idaho 83467
    • Office Phone:  208-756-2815 ext 282         
    • Fax: 208-756-6915     
    • Cell: 208-993-095 0

County Contact Information

  • Butte County Extension Office
    • Address: P.O. Box 832 (159 N. Idaho St.)
    • Arco, ID  83213-0832
    • Phone: (208) 527-8587
    • Fax: (208) 527-3036
    • Email: butte@uidaho.edu
    • Web Address: http://extension.uidaho.edu/butte/
  • Custer County Extension Office
  • Lemhi County Extension Office
    • Address: 200 Fulton St., Suite 202
    • Salmon, ID  83467
    • Phone:(208) 756-2815 ext 284
    • Fax:(208) 756-6915
    • Email:lemhi@uidaho.edu
    • Web Address: http://extension.uidaho.edu/lemhi/

Contact Lost Rivers Cooperative Weed Management Area

Contact Lost Rivers Cooperative Weed Management Area

Brad Gamett, Executive Board Representative
Butte County Weed Superintendent
PO Box 832
Arco, Idaho  83213
Phone: 208-527-8595
Cell Phone: 208-589-0656
Fax: 208-527-3469


Service Area

Services provided in:
  • Butte County, Idaho
  • Custer County, Idaho
  • Lemhi County, Idaho

To request additions or corrections to this entry email the Administrator
1 Introductory article was found for Lost Rivers Cooperative Weed Management Area

pdf Lost Rivers Cooperative Weed Management Area: 2009 End-of-Year Report