Appalachian View (IMAGE) Penn State Caption The forest inventory plots in the Ridge and Valley physiographic province in Pennsylvanias used in this study are shown. Inventory plots were restricted to land owned and managed by the Pennsylvania Department of Conservation of Natural Resources Bureau of Forestry and the Pennsylvania Game Commission, underlain by shale and sandstone bedrock. Credit Margot Kaye Research Group, Penn State Usage Restrictions non commercial use only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.