6. Six-Mile Canyon, Six-Mile Reservoir and Spring
Land Manager: Sawtooth National Forest
Legal Location: T 15S R 28E Sections 11, 14, 15, 16 Cassia County
Forest Division: Black Pine
Dominant Plant Community Type: Shrub-Juniper/Aspen
Impacts: Livestock have accessed the reservoir area and trampled the inlet region, leading to vegetation loss and erosion. Impacts from utilization have severely impacted young willows along the creek below the reservoir. A small exclosure in the upper canyon does protect some of the Six-Mile Spring location, but the site still shows extensive impacts from past utilization. Impacts to upper portions of Six-Mile Canyon range from moderate to severe, depending on the location. Impacts include loss of riparian species, loss of riparian and aspen regeneration, loss of the riparian greenline, and loss of fisheries values. In some stretches the channel has been widened; at other locations down-cutting and head-cutting are occurring.
Recommendations: It is recommended that livestock be permanently excluded from the reservoir site. The value of the location for fish, wildlife, and recreation should preclude livestock utilization. Livestock should be withdrawn from the remainder of the drainage until substantial riparian and aspen recovery and regeneration have been achieved. Recovery will require a minimum of 3-6 years. Riparian shrubs and aspen saplings need to achieve a height of 6 feet or more in order to withstand short duration grazing impacts.
List of Figures:
1. Impacts to hydric zone near reservoir.
2. Impacts to younger riparian species, lower canyon area.
3. Utilization impacts outside spring exclosure site.
4. Loss of riparian structure; erosion and loss of channel features.
