Forest Restoration Potential Using Ecological Site Descriptions.

The USDA-NRCS uses Ecological Site Descriptions (ESD) to help incorporate the story of soil, climate, floral, faunal, and human interactions into schema for land management decision-making. We have developed a novel use of digital soil mapping techniques and ESD concepts to estimate historical forest composition and forest floor carbon dynamics in the high-elevation forests of the Central Appalachians within the Monongahela National Forest (MNF), West Virginia (WV). This region was extensively disturbed by clear-cut harvests and related fires during the 1880’s-1930’s. Spodic soil morphology, which is considered indicative of conifer influenced ecological sites (ES), was mapped and showed correspondence to red spruce – eastern hemlock (Picea rubens – Tsuga canadensis) forest communities in local witness tree records from 1752-1899. These data and resulting models indicate a greater spatial extent of spodic soil properties than documented in previous soil maps, which is more consistent with theories of much more extensive historic spruce populations. The resulting maps and models provide guidance for restoration to mimic historic forest composition in MNF. Using the ESD developed for this area, our results suggest that historic disturbance probably induced state transitions to hardwood forest along the conifer-hardwood ecotone that runs along the Appalachian Mountains.  Data also suggests that historic spruce dominated stands in WV converted to a hardwood state by historic disturbance have lost considerably more than 10 centimeters of O horizon thickness (mor forest floor) along the regional conifer-hardwood ecotone, and 21 centimeters or more along the highest ridgelines. We estimated that at least 3.74-6.62 Tg of carbon were lost from areas above 880 meters elevation in WV due to historic disturbance of O horizons, and that these stocks and related ecosystem functions could potentially be restored in 80 years under most favorable management.