Principle impacts to the Nez Perce (Neeme‐poo or Nimi’ipuu) NHT, the only NHT in the Planning Area, and Other Historic Trails arise directly from development activities and intrusions into the viewshed that alter the environment that contributes to the trail’s significance. Alternative B provides the greatest protection for these trails through the application of larger buffer zones for surface-disturbing activity (both NSO and CSU) and restrictions on motorized vehicle use. The larger acreage of special designations and limited resource use under Alternative B reduce the potential for direct and indirect adverse impacts. Alternative C allows the greatest resource use, and provides the least protection through special designations, but does provide more effective proactive management, including NSO and CSU restrictions, than Alternative A. Alternative A, the existing management, includes the least effective proactive management, in part because of the change in understanding of the adverse impact of viewshed intrusions that has evolved since this management was developed. However, management under Alternative A would result in less resource use than Alternative C, and adverse impacts would likewise be less under this alternative. Alternative D provides protection similar to Alternative B, but emphasizes viewshed protection that would result in a reduced potential for adverse impact than alternatives A and C, but more than Alternative B.