1. Understanding systematic variability of soil properties and deep regolith in the Southern Sierra CZO Toby O’Geen, UC Davis Subalpine forest 3000 m Mixed Coniferous Forest 2000 m Pine/Oak Forest 1100 m Oak Savannah 400 m

2. Subalpine forest 3000 m Mixed Coniferous Forest 2000 m Pine/Oak Forest 1100 m Oak Savannah 400 m Degree of Weathering Elevation (m) 400110020003000 Deep regolith Soil Regional patterns in soil development and regolith thickness 11002000 3000

3. Some pedologic questions: What are the dominant factors controlling soil development across the gradient? It may not be what previous studies thought. What is the extent of soil variability within each catena? Soil Variability at San Joaquin Experimental Range Depth

4. Some deep regolith questions: What soil forming factors are most important in describing spatial patterns in regolith thickness? Do quantifiable proxies exist (i.e. terrain attributes, solar radiation models, gamma-ray imagery)? How variable is regolith thickness within each catena? To what extent do terrain attributes describe this variability? How do other regolith characteristics very across the CZO transect?