Endangered Species Project
Salmonid Habitat Locations for California

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On January 22, 2004, the U.S. District Court for the Western District of Washington at Seattle imposed no-use buffer zones around salmon-supporting waters (as defined by the court) in Washington, Oregon, and California for certain pesticides. In 2014, U.S. EPA launched the Salmon Mapper Site, an interactive mapping website to help pesticide users better understand the court-ordered buffers.

The court’s order will remain in effect for each pesticide listed below until any of the following occur:

  1. The U.S. Environmental Protection Agency (U.S. EPA) determines that these pesticides have no effect on listed Pacific salmon and steelhead, or
  2. U.S. EPA makes a determination that these pesticides are not likely to adversely affect these species, or
  3. U.S. EPA completes consultation with the National Marine Fisheries Service about the potential effects of the pesticides on Pacific salmon and steelhead.

Meanwhile, under the court order, no-use buffer zones of 20 yards for ground applications and 100 yards for aerial applications apply from the edge of salmon-supporting waters for use of the following active ingredients (and sample trade names*):

1,3-Dichloropropene (Telone) Diflubenzuron (Dimilin) Methyl Parathion (Penncap-M)
2,4-D (Weedar 64) Dimethoate (Cygon) Metalochlor (Dual)
Acephate (Orthene) Disulfoton (Di-Syston) Metribuzin (Sencor)
Azinphos-methyl (guthion) Diuron (Karmex) Naled (Dibrom)
Bensulide (Prefar) Ethoprop (Mocap) Oxyfluorfen (Goal)
Bromoxynil (Buctril) Fenbutatin-oxide (Vendex) Pendimethalin (Prowl)
Carbaryl (Sevin) Lindane (Lindane) Phorate (Thimet)
Carbofuran (Furadan) Linuron (Lorox) Prometryn (Caparol)
Chlorothalonil (Bravo) Malathion (Malaspray) Propargite (Omite)
Chlorpyrifos (Lorsban, Dursban) Methamidophos (Monitor) Tebuthiuron (Spike)
Coumaphos (Agridip) Methidathion (Supracide) Tryclopyrester (Garlon 4)
Diazinon (Spectracide) Methomyl (Lannate) Trifluralin (Treflan)

*This list may not include every trade name for each active ingredient. Always check the active ingredient list on the label to verify presence of the above ingredients.


For more information:



If you have more questions about these requirements, contact:
Anita Pease
USEPA Headquarters
Ariel Rios Building
1200 Pennsylvania Avenue, N.W.
Mail Code: 7507P
Washington, DC 20460
Phone: (703) 305-0392
E-mail: Pease.Anita@epa.gov