1. Impact of Western Juniper on Hillslope Hydrology: Steens Mountain, OR
USDA-ARS Rangeland Research Unit
Burns, OR
USDA-ARS Northwest Watershed Research Unit Boise, ID

2. Background 8.5 million acres in western juniper woodland
95% of the woodlands are 100 years old or less
Juniper invasion results in
Significant reductions in shrub/understory production and cover
Reduced plant diversity
Loss of wildlife habitat
Increased erosion potential

3. Project Info
Rainfall simulation plots were run on eight replicates of cut and uncut treatments.

4. Vegetation Response
Cut plot
Un-cut plot

5. Trough Water
Cut plot
Un-cut plot

6. Removing Juniper decreases runoff volume
Photos

7. Removing Juniper reduces sheet erosion
Photos

8. Conclusion
Juniper invasion can result in a dramatic increase in runoff and erosion. The severity of erosion will likely be related to the loss of understory cover and the erosion potential of a site.

9. Questions? For more information contact: Jon Bates or Tony Svejcar,
USDA-ARS Rangeland Scientists
(541) or
Fred Pierson
USDA-ARS Research Hydrologist
(208)