Response of Understory Vegetation following Western Juniper (Juniperus occidentalis) Cutting on Two Sites Breanna S Sabin FS 533

Overview  Western Juniper Expansion  Research Sites  Response to Juniper Removal  Conclusion

Western Juniper Expansion Miller et al Juniper has occupied its current range for several thousand years, but in the past 130 years it has rapidly expanded into neighboring communities This has caused increased soil erosion, reduced stream flow, reduced forage reduced stream flow, reduced forage production, altered wildlife habitat, changed plant communities composition, structure and biodiversity Control methods are now being explored to combat this problem – prescribed fire, to combat this problem – prescribed fire, cutting and herbicide, we will concentrate on cutting

Research Sites  John Day : short and long term study -Mixed size classes -Three paired plots (2000m²) -Trees were removed on one paired plot and left on the other  Steens Mountain: short term -Eight,.8 hectare plots, tree were cut on half of each plot were cut on half of each plot -Site was dominated by 80 yr old juniper, perennial plant old juniper, perennial plant basal cover was about 2.5%, basal cover was about 2.5%, dominate understory (75%) dominate understory (75%) was Poa sandbergii was Poa sandbergii Miller et al. 2005

Short-Term Response John Day Sites 1984 Steens Mountain Eddleman 2002, Bates 1998

Long-Term Response  John Day Sites -After 18 years -After 18 years -Uncut woodland plots showed little change in herbaceous composition and measurable decreases in density and cover of shrubs showed little change in herbaceous composition and measurable decreases in density and cover of shrubs -Cut treatments had large increases in shrub and perennial grass cover and density -Perennial grass took over the cheatgrass

Conclusion  Cutting has proved to have a positive impact on the plant community as well as the soil. -soil water content and plant water availability also increased with cutting  Results indicate that restoration of Western Juniper sites requires patients to achieve a desired plant community Questions?