Slickspot peppergrass is a flowering plant unique to Idaho.

It is threatened with exinction by non-native weeds caused by livestock trampling and grazing, road construction and off-road vehicles in the Snake River Plain, Owyhee Plateau and nearby foothills in southwestern Idaho.

1999 FWS noted that slickspot peppergrass qualified as a candidate species under the ESA.

2000 FWS recommended listing the plant as endangered.

2002 WWP and Committee for the Hight Desert filed lawsuit to compel FWS to issue a final rule on listing slickspot peppergrass under the ESA; settlement reached to issue rule by July 2003.

July 2003 FWS delayed listing decision for six-months based on objections from Air Force ecologist (military training operations out of Mountain Home Air Force Base would be affected if peppergrass were listed under the ESA).