Mining Distributed Legacy Data to Build Soil Class and Property Maps Across PacNW Forests.

Most of the National Forest land in the Pacific Northwest region, about 17 of 25 million acres in Oregon and Washington, lacks detailed soil survey (SSURGO) map data. To address this void we have inducted all legacy Forest Service soil resource and landtype survey data for the region, nearly of which was only present in paper form, to an ArcGIS geodatabase for agency and public use. Blending these data and locally overlapping SSURGO, we developed total-region digital maps of soil classes and properties. Using predictive digital soil mapping (CART and Random Forests) and ground truth surveys, we infilled gaps, harmonized map units, and estimated map accuracy. National Forest managers will have these soil data for planning purposes from now until such date as the SSURGO mapping is completed.