In 1991, to capture the SRI data digitally, the original overlays were traced (1:1) onto clear film, including only the line work, excluding the codes and the symbology showing special features such as cliffs, springs, etc. In the Summer/Fall of 1991, these manuscripts were scanned using the Houston Instruments plotter/scanner and were processed in LTPlus for transfer to MOSS and later to Arc. Digital processing was completed for the forest in 1994.
For mapping units ending in 'M': "Mt. Baker National Forest Soil Resource Inventory, Pacific Northwest Region, September, 1970"
For mapping units ending in 'S': "Snoqualmie National Forest Soil Resource Inventory, Pacific Northwest Region, August 15, 1972"
Please contact the Data Steward for availability.