 Between 1879 and 1885, one change added territory on the Camas Prairie from Nez Perce while another brought back territory in present-day Adams, Valley, Custer, and Lemhi counties in the south.In 1887, territory was exchanged with Boise County dividing present Valley County between the two counties.One change in 1889 transferred territory to Custer County while another change finalized the county's northern border at its present location.