Soil Influence on Dry Forest Vegetation Patterns and Productivity in the Eastern Cascade Mountains of Oregon.

Soils influence vegetation and can critically affect forest restoration results. Areas with similar parent materials can have changes in soil and vegetation across a slope, aspect, slope position, microtopography, and elevation. The objective of this project was to assess what soil characteristics influences vegetation productivity, patterns, and species. The study area for this project is located in the dry forests of the eastern slopes of the Cascade Mountains in the Fremont Winema National Forest of Southern Oregon and overlaps with a Forest Service NEPA project planning area called the Lobert Restoration project. Five distinct vegetation association types (ponderosa pine, Douglas -fir/ponderosa pine, aspen/lodgepole pine, and ponderosa pine-juniper/mountain mahogany) were chosen to represent the dominant vegetation types in the project area. In each of the vegetation association types, four replicated sites were characterized for soil, vegetation, and landforms. Soils were described at each site. Moisture and temperature loggers were also placed in the soils to track the influence of water availability on vegetation. The soil properties, depth, moisture and vegetation for each site will be compared to determine a causal relationship between soil characteristics and vegetation pattern, productivity and species. This project will provide insight into soil characteristics and vegetation within the Lobert Restoration project area for the purpose of forest restoration planning.