Ozette Prairies, Tree encroachment, Prairie Invasion, Subsurface stratigraphy, Wetland analysis
The objective of this research is to evaluate the wetland and forest dynamics in and around the Ozette Prairies to identify their origin and history since the Last Ice Age. The Ozette Prairies are treeless areas, dominated by unique associations of understory species in an otherwise heavily forested region. The prairies are historically (pre-European) persistent elements of the landscape in a region where the climate promotes forest growth. Presently, the prairies are undergoing encroachment by the surrounding forest. The patchy character of the vegetation attests to centuries, or more, of climate change, expansion and demise of forest populations and changing fire regimes. We used a suite of methods to address the environmental history of this landscape. The first phase of this project evaluated the soils of the vicinity (this research is on-going). The soils indicate that fire has been an important component in their formation. The second phase of the project begins to evaluate the incidence of fire on this landscape. Three approaches where taken: examining sediments accumulated in wetlands within the prairies, examining repeat aerial photographs of the prairies to document tree invasion, and vegetation sampling to identify tree demographics.
Report to Olympic National Park
Bach, Andrew and Conca, Dave, "Natural History of the Ahlstrom’s and Roose’s Prairies, Olympic National Park, Washington" (2004). Environmental Studies Faculty and Staff Publications. 13.